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The Teachers - Manual 

AND 

PUPILS' TEXT BOOK 

ON 

Anatomy, Physiology and Hygiene. 

INCLUDING THE EFFECTS OF 

ALCOHOL AND NARCOTICS UPON 
THE HUMAN SYSTEM, 

DESIGNED TO ACCOMPANY 

The Teachers' Anatomical Aid 
/ 

5 PROF. J. K.'RASSWEILER, A. M. 




BY 

Central School Supply House, 
chicago, illinois. 



Y 









Entered according io Act of Congress, in the year 1889, 

By Central School Supply House, 

in the office of the Librarian of Congress, at Washington, D. C. 



PREFACE. 



This book is intended to go into the schools of 
the country as a companion to the " Teachers' Ana- 
tomical Aid," which is supposed to be before the 
class during every exercise or recitation in Physi- 
ology, and to which the illustrative references, found 
throughout these pages, relate. 

To the teacher who gives oral lessons in Physi- 
ology, by the use of the Aid, this volume offers 
assistance in presenting the truths of the science in 
proper order, plain language, and with many illus- 
trations gathered within the range of the pupils' 
observation and experience. Thus, even inexperi- 
enced teachers are furnished with methods and 
material to conduct a well-arranged course of daily 
drills on a subject of surpassing importance and 
interest. 

To the teacher who conducts a recitation, with the 
use of the Aid, this work offers guidance in point- 
ing out, precisely, by its frequent references, those 
parts or features on the plates or manikin sections, 
which illustrate any topic in hand, as found in the 
current text-books on Physiology. 

While this book is thus intended to be helpful to 

(1) 



2 PREFACE. 

teachers of all grades of experience, it is, at the 
same time, adapted for use as a text-book for ele- 
mentary classes. The practical results which may 
be obtained from such a use of it, in connection 
with the Anatomical Aid, will be found to be more 
satisfactory than those which can be attained by any 
other method of instruction in the elements of 
Physiology. 

When used as a text-book with the Aid, the latter 
should be made conveniently accessible to the 
pupils. This can easily be done in any school- 
room. The objection that the pupils will injure the 
charts by handling them, is a mischievous notion. 
They are entitled to such privileges. If well and 
kindly advised, they will handle them properly and 
w T ill take pride in carefully preserving them from 
injury. 



TABLE OF CONTENTS. 



THE SKELETON. 

PAGE. 

Bones— Like the Framework of a House— Number of Bone3— Shape- 
Structure— How United— Bound Together by Ligaments— Uses 
of the Bones — Division of the Skeleton — Table of the Skeleton — 
Bones of the Head— The Skull— The Face— Bones of the Trunk— 
The Spinal Column— Vertebrae — The Chest— The Pelvis— Bones of 
the Upper Extremities — The Shoulder— The Arm— Bones of the 
Lower Extremities— The Thigh — Lower Leg and Foot — Health of 
the Bones— Outline— Questions 5 

THE MUSCULAR SYSTEM. 

The Muscles— Number and Structure of Muscles— Tendons— Use of 
the Muscles— Language of the Muscles — Two Kinds of Muscular 
Action — How Muscles Act— Antagonists or Counter Muscles — 
Some Prominent Muscles and Their Names— Health of the Mus- 
cles— Outline— Questions 19 

THE NERVOUS SYSTEM. 

The Brain - Structure — Protection to the Brain— Divisions of the 
Brain— Hemispheres — Work of the Cerebrum— Work of the Cere- 
bellum—The Spinal Cord— The Nerves— JNervous Action— Reflex 
Nervous Action— Sympathetic Nervous Action— Health of the Ner- 
vous System— Outline— Questions 29 

THE SPECIAL SENSES. 

Nerves of Common Sensation— Nerves of Special Sensation— The 
Eye— Protection of the Eye— Tear Apparatus— Thp White Coat of 
the Eyeball— The Black Coat— The Nervous Coat— Tup Humors of 
the Eye— The Ear— The Nerve of Hearing— The Outer Far— The 
Middle Ear— The Inner Ear— How We Hear— The Sense of Smell — 
How We Perceive Odors — The Sense of Taste— The Tongue — How 
We Perceive Taste— Outline— Questions 41 

THE CIRCULATORY SYSTEM. 

Organs of the Circulatory System— The Heart— The Arteries— The 
Veins — The Capillaries — Blood Change in the Capillaries— The 
Course of the Blood — Three Divisions of the Circulation— Inter- 
esting Facts— Health of the Circulatory System — Outline — Ques- 
tions 54 

THE RESPIRATORY SYSTEM. 

Structure of the Lungs— Use of the Lungs— Breathing— How We 
Breath— Chief Breathing Muscles— Pleura— Health of the Respira- 
tory Organs— Exercise— Impurities of the Breath— Ventilation— 
The Voice— The Larynx— An Experiment— Speech— Outline — 
Questions 62 



4 CONTENTS. 

THE DIGESTIVE SYSTEM. 

Body— Building from Blood— Aid of the Muscular System— Work of 
the Teeth —Number of Teeth— Structure of a Tooth— Work of the 
Salivary Glands — Work of the Pharynx and Oesophagus — Work of 
the Stomach — Use of the Gastric Juice— Work of the Pylorus — 
Work of the Liver — Work of the Pancreas — Health of the Diges- 
tive System —Eating too Fast— Eating too Much — Eating too Fre- 
quently— Eating Indigestible Food— Exercise— Outline— Questions. 71 

THE ABSORPTIVE SYSTEM. 

Absorption — Intestinal Villi— Two classes of Absorbents in the Villi — 
Veins in the ViJli -Portal Circulation — The Second Route — Lac- 
teals in the Villi — Chyliferous Vessels and Lymphatic Glands — 
Thoracic Duct — What Has Been Done — Assimilation — Recapitula- 
tion — The Lymphatic Vessels— Lymph— Origin of Lymph— The 
Lymphatics— The Lymphatics a System of Drainage— The Lym- 
phatic Glands— The Lacteals, a part of the Lymphatics — Lympha- 
tics Compared with the Blood Vessels— Other Functions of the 
Lymphatics— Suggestions to the Teacher— Outline — Questions 87 

THE EXCRETORY SYSTEM. 

Excretory Organs— Impurities Thrown Off by the Lungs— Carbon Di- 
oxide — Carbon Acid Test — Test of the Breath — Watery Vapor Ex- 
haled — The Liver— As an Excretorv Organ — The Kidneys — Work 
of the Kidneys— The Kidneys at Work — Difference Between the 
Secretions of the Liver and Kidneys 93 

MICROSCOPIC LESSON. 

Its Purpose— The Microscope as an Aid in Physiology— M icroscopic 
Structure of the Arteries— Of the Veins— Of the Capillaries— Of 
the Mucus Membrane— Of the Looped Capillaries of the Skin— Of 
the Intestinal Villi— Of the Air Cells of the Lungs— Capillaries 
of the Parotid Gland, Brain and Cellular Tissue— Of trie Elastic 
Tissues, Muscular Fiber and Bone Corpuscles — Of Voluntary Mus- 
cles— Of the Glands of the Stomach— Of the Nerve Fibers of the 
Brain— Of the Hepatic Vein— Of the Kidney Structure— Of Red 
Blood Corpuscles— Of Tendinous Fiber— Adipose Tissue— Epithe- 
lial Cells— Cells of Epidermis— Pigment from Choroid Coat of 
Eye— Other Views 98 

EFFECTS OF ALCOHOL. 

Value of a Sound Body— Abuse of the Body— Strong Drink— Alcohol 
and What is It! What is Its Origin— How is It Done— Fermenta- 
tion — Acetous Fermentation — Beer from Barley— Distillation — 
Two Classes of Strong Drink— A Healthy Stomach— Inflamma- 
tion -Ulceration— Last Stages of Alcohol Poisoning— Alcohol 
and the Liver— The Result— Alcohol and the Kidneys— Effects on 
the Brain— The Brain the Seat of the Mind— Consequences- Alco- 
holic Softening of the Brain— Delirium Tremens— Effect on the 
Nerves— Different Effects of Intoxicants upon the Heart— Synop- 
sis— What It Will not Do 106 

TOBACCO AND ITS EFFECTS. 

Tobacco is a Poison— Its Effects upon the Young— Cigarette Smoking— 
An Experiment — The Respiratory Organs— How Affected— Con- 
clusion ...... 119 



Framework 
of a House. 



THE SKELETON. 



BONES. 

Like the The framework of the body is com- 

posed of bones and ligaments. It is 
called the skeleton. What beams, joists 
and rafters are to a honse, bones are to the body. 
As each timber in the framework of a building is 
fitted for its own particular place and purpose, so 
each one of the bones of the body has its own place 
and is in every way precisely adapted, in shape and 
strength, for a special use. 

There are two hundred and eight bones 
^T be J« in the skeleton. This does not include 

or Bones. 

the teeth, for they are really not a 
part of the skeleton. Thirty-four of the bones of 
the body are single — only one of the same kind. 
Besides these, there are eighty-seven pairs, the two 
bones of each pair being alike — one on each side of 
the body. 

The skeleton plate shows that the bones 

are very different in shape. Some are 

long, like this (leg bone), for example. Others 

(5) 



6 ELEMENTARY PHYSIOLOGY. 

are nearly round, like these bones of the wrist. 
Some are quite flat, like this large, spreading bone 
at the shoulder (16), or these broad bones in the 
lower part of the main body (3). 

structure ^ ie ^ ones are Yei 7 hard an d strong. 
"Hard as a bone" is a familiar compar- 
ison. We shall not be surprised at their hardness 
and strength when we shall have learned what im- 
portant uses they serve in the body. There are two 
kinds of material in the structure of a bone. One 
part is called animal matter and the other is called 
mineral matter. If the bone were composed of 
animal matter alone, it would bear no pressure and 
keep no permanent shape. If it were made entirely 
of mineral matter it would be too brittle, and conse- 
quently would break very easily. So these two kinds 
of material are united together in such a way as to 
secure strength without too great brittleness. In 
childhood the bones are not easily broken. This is 
because in early life they contain about twice as 
much animal matter as mineral matter. What a wise 
protection against the "bumps" and "tumbles" of 
the little ones. In middle life the two kinds of 
material are more nearly equally divided. In old 
age, however, the bones are very brittle, because, 
then, there is about twice as much mineral matter as 
animal matter in their structure. 

It is an easy and interesting experiment to sepa- 
rate these two kinds of bone material. Throw a flat 
bone, or piece of bone, into the fire. After a while 



THE SKELETON. 7 

you will find a part of it, like a cinder, among the 
ashes. This is the mineral part. The fire has 
burned out the animal matter. Take the "drum- 
stick" bone of a chicken and place it in a bottle con- 
taining a mixture made by filling the bottle half full 
of water and adding about half as much muriatic 
acid — a common drug which you can get for a trifle 
at the nearest drug store. This will take out the 
mineral matter from the bone and leave the animal 
matter. The mineral matter which you took from 
the fire was brittle or crumbling. The animal 
matter, when taken from the acid, is gluey and can 
be wound, like a cord, about the finger. The broad 
or flat bones, like those of the head, are not entirely 
solid. Between the two outside layers of such a bone 
there is a layer of spongy-like material. These 
three layers of structure in a flat bone can be clearly 
seen by looking at the edge of such a bone which 
has been sawed through. 

The long bones are generally hollow and contain 
a substance called marrow. At the ends they are 
usually thicker and more spongy. This serves to 
break the force or shock of heavy stepping or jump- 
ing with the lower limbs, or a hard stroke with the 
arm. The ends of the long bones are also covered 
with a smooth, white substance called cartilage. 
This aids in giving the bone an easy motion at the 
joint where it is united to another bone. 



8 ELEMENTAR Y PHYSIOLOGY. 

The bones are united to each other in 
United, different ways. Those which are quite 
movable are connected by joints. Some 
of these are called hinge- joints because they work 
like the hinge of a door. These (arm) bones 
which meet at the elbow are hinge-jointed. Raise 
and lower your forearm and notice particularly how 
the joint acts. The joints in the fingers and the 
knee are also hinge-joints. Another kind is called 
the ball and socket joint, where the round end of one 
bone moves in a hollow place of another. Here (a) 
at the hip is a good example of a ball and socket 
joint, where the round head of this large upper bone 
of the leg moves in a deep hollow of this lower bone 
of the main body. The bones of the head meet each 
other with jagged edges forming a seam-like junc- 
tion called a suture. One of these is clearly shown 
on this skeleton (12). Between the bones of the 
back are placed cushions of cartilage. This is a 
substance softer than bone and quite elastic, like 
rubber. This cushion arrangement between the 
bones of the back, is nicely shown on this plate. 
(Refer to cartilages between lumbar vertebrae.) 

The bones are bound to one another 

Bound To- _. __ 

getner by by ligaments. These are very strong 
Ligaments. an( j YuAdi. the bones firmly in position. 
Some of these stout bands or ligaments are shown on 
this plate. Here (XVI) are the ligaments which 
bind together the bones of the hip. These (XXV, 
XXVI) are the ligaments of the elbow joint. 



Fses of 
the Bones. 



THE SKELETON. 9 

The bones of the body serve several 
important purposes. 1. They give the 
body its general shape. 2. They sup- 
port the softer material of the body within and 
around them. 3. They protect delicate and impor- 
tant parts against injury from without, as, for exam- 
ple, the brain, lungs and heart. 4. They serve as 
levers, to be moved by the muscles in the various 
movements of the body, as we shall learn more 
clearly, somewhat later. 

Division ^Y l °king a ^ the figure of the skeleton 
of the we perceive that the bones are grouped 

Skeleton. • , x r> .lit** i i 

into tour natural divisions, namely: 1. 
The bones of the head. 2. Those of the main body, 
or trunk. 3. Those of the upper extremities, or 
arms. 4. Those of the lower extremities, or legs. 

We have now learned about the number, shapes, 
material, union, uses and groups of the bones of the 
skeleton. We are now ready to study the more 
important bones of each group more closely. 



10 



ELEMENTARY PHYSIOLOGY. 




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THE SKELETON. 11 

BONES OF THE HEAD. 

There are twenty-two bones in the head. 

The Skull. 

Eight of these are shaped and united in 
such a way as to form a sort of round box which is 
called the skull, or cranium. This is one of the most 
important parts of the skeleton, since it contains the 
brain, the most delicate organ of the body. The 
word organ, in physiology, means any single part of 
the body which serves a special purpose. Thus, the 
brain, heart, lungs and veins are organs. The skull ? 
or brain-box, is placed, like a dome, at the top of the 
structure of the body. It is wonderfully fitted for 
the protection of its tender contents. It is shaped 
for strength as well as for beauty. 

The front of the skull is formed by the frontal 
bone (1), or bone of the forehead. The two parietal 
bones (2) form the upper sides, and the two tem- 
poral bones (3) form the lower sides of the skull. 
At the back of the head (4, back view of skeleton) 
is the occipital bone. Two more of the skull bones 
form its lower part or base. These we will not 
name here; but you will find them named in the full 
table of the bones which has been given. 
_ „ The remaining fourteen bones of the 

The Face. & 

head give shape to the face. The two 
nasal bones (6) form the bridge of the nose, and the 
two malar bones (4) the prominence of the cheeks. 
The upper jaw is formed of the two upper maxillary 
bones (7). The lower jaw bone (8) is called the 



12 ELEMENTARY PHYSIOLOGY. 

lower maxillary. The teeth are set in sockets of 
these maxillary bones. 

BONES OF THE TRUNK. 

The main body is called the tru?ik. The upper 
part of the trunk is fitted to contain the lungs and the 
heart. Its lower part contains the stomach, liver and 
bowels. 

The great pillar of the body is the spinal 
column. column. It bears aloft the head — the 
crowning part of the whole structure. It 
supports the great vital organs of the main body. 
It is most wonderfully constructed with reference to 
comfort and safety of life. Instead of being com- 
posed of but one or a few bones, it is built up of 
twenty-six pieces, which, while laid up one above the 
other, are separated from each other by very elastic 
cushions of cartilage. This does not only make the 
back- bone capable of bending forward, backward and 
sideways, but it makes the whole pillar springy, so 
that the delicate brain which rides at its summit is 
not affected by jarring from the heavy movements of 
the body. 

Twenty-four of the bones of the spinal 
column, or back, are called veriebrce 
These are firmly bound together by ligaments and 
interlocked with each other by their own projecting 
parts. An opening runs through each vertebra. 
These openings form the spinal canal through which 



THE SKELETON. 13 

the spinal cord, of which we shall learn hereafter, 
passes. The vertebrae are divided into three sets. The 
seven upper ones are in the neck. The next twelve 
are in the back proper; to these the twelve pairs of 
ribs are attached. The five lower vertebrae are in 
the region of the loins. They are very stout, as the 
figure shows, just as we would expect them to be, 
since they support a large part of the weight of the 
body. 

The upper part of the trunk, which con- 
tains the heart and lungs, is called the 
chest. The skeleton of the chest is formed behind, 
as you see, by the middle division of the spinal col- 
umn; on the sides by the rifts (12, 13), and in front 
by the sternum (10) or breast-bone. Here, again, we 
find a wise provision for the protection of life. The 
breast-bone is not near so hard as most of the other 
bones. It is consequently more flexible. The ribs 
are not directly united to the sternum, but are joined 
to it by cartilages. By these means, a heavy blow 
on the breast, which otherwise would seriously injure 
the organs within, is made comparatively harmless. 
The plate of the skeleton shows that the ribs are 
not all joined to the breast-bone in front. Seven 
pairs (12-13) are so joined. These are called true 
ribs. The remaining five pairs (14-15) are called 
false ribs. 

The bones of the lower part of the trunk 

The Pelvis. , , , . . , . 

are shaped and joined so as to torm a 

large bowl-shaped cavity. This is called the pelvis. 



14 ELEMENTARY PHYSIOLOGY. 

Notice how broad and peculiarly formed these two 
(3) bones are. The sacrum (1) bone is wedged 
between these two bones at the back. 

BONES OF THE UPPER EXTREMITIES. 

The In examining the shoulder, we first notice 

shoulder, these two collar-bones (8). Their use is 
to brace the shoulders properly apart ; so one end 
rests against the breast-bone and the other against 
the shoulder. Next comes the shoulder-blade (16). 
These are so broad to allow the attachment of some 
very strong muscles of the upper part of the body. 
The upper arm has one large bone called 

The Arm. 

the humerus (1). The radius (2) and the 
ulna (3) are the bones of the lower arm. There 
are eight roundish little bones in each wrist (4), five 
longer ones in the middle of each hand (5), three 
short bones in each finger (6, 9, 10) and two in each 
thumb (7, 8). 

BONES OF THE LOWER EXTREMITIES. 

Here we meet the largest bone of the 
skeleton (1). It is called the femur. 
Observe the round shape of its upper end (a). This 
is called the head of the femur. Moving in a hollow 
place of this large bone (3) ,it forms the ball and socket 
joint of the hip. Do not fail to notice how securely 
the lower limbs are bound to the main body by these 
numerous strong ligaments. 



THE SKELETON. 15 



The lower leg has two bones — the tibia 

and Foot. 



(a), and the fibula (b). The knee-joint, 



between the thigh bone and the bones of 
the lower leg, is protected by a flat bone called the 
knee-pan (2). There are seven bones in each heel, 
five in the middle part of each foot, three in each of 
the larger toes, and two in each great toe. 

Notice this peculiarity in the form of the foot. It 
is curved or arched from the heel to the front. 
Here is another arrangement for springiness, with- 
out which, walking would not only become clumsy 
but painful. 

The bones of a grown person are so much 
th^Bones. hardened by the mineral matter which 

has increased in their structure, that they 
are not easily changed in shape. They are more 
easily broken than bent. Neither is the full-grown 
joint likely to change in shape and character during 
the active years of life. So the general carriage of 
the body in adult life, depends on the habits and 
circumstances which shaped it in youth. We have 
learned that in childhood the bones are quite flexible 
and disposed to bend, instead of breaking, under a 
strain. For this reason, children who begin to walk 
very early become more or less bow-legged. Pupils 
who are in the habit of leaning forward on the desk, 
in school, will certainly, more or less deform their 
bodies. If a boy, in walking, carries his body in a 
lazy, stoop-shouldered position, he will go bent and 
deformed through life. Avoid leaning the body 



16 



ELEMENTARY PHYSIOLOGY. 



forward in sitting. When lying down, do not 
bolster up the head with high pillows. While stand- 
ing or walking, hold the head erect, throw the shoul- 
ders back, and take in full breaths of air. If these 
positions in lying, sitting, standing or walking are 
carefully kept in youth, all the curvings and efforts 
of the body and limbs which come from ordinary 
labor, will not injure them, and the full-grown figure 
will be straight, graceful and strong. 

OUTLINE. 

THE BONES OF THE SKELETON. 



WHAT? 



Framework of the body. 

208. Eighty-seven pairs. Thirty-four single. 

Shapes: Long, flat, round, irregular. 

Composed of animal and mineral matter. 

United by joints, sutures aod cartilages. 

Bound together by ligaments. 

Arranged in four groups: 

Head, Trunk, Upper and Lower Extremities. 



f Twenty-two in the head. 
I Fifty-four in the trunk. 
where? -I Sixty-four in the upper extremities. 
Sixty in the lower extremities. 
^ Eight in the ears. 



WHY? 



r To give shape to the body. 

To support the softer parts of the body within and 
around them. 

To protect important organs. 
t To serve as levers to be moved by the muscles. 



THE SKELETON. 17 

SUGGESTIONS TO THE TEACHER. 

Be sure that the acid and burning experiments on the com- 
position of bones are performed either by yourself or by the 
pupils. Get a piece of flat bone sawed to show the layers. 
Get a leg joint at the butcher's; remove muscles and tendons, to 
show the ligaments; then sever the bones at the joint to show 
cartilage. Show a fresh piece of long bone containing marroic. 

TEST QUESTIONS. 

Of what is the skeleton composed? 
To what parts of a house are the bones compared? 
How many bones in the skeleton? 
Do the teeth belong to the skeleton proper? 
How many single bones in the body? 
How many are in pairs? 
What variety of shapes have the bones? 
What two kinds of material in the bones? 
Which material makes the bone flexible? 
What is the effect of the mineral matter? 
How do these materials vary at different ages? 
What wise provision in this arrangement? 
Why are the ends of the long bones more spongy? 
Why are they covered with cartilage? 
In what ways are the bones united? 
Locate a hinge-joint of the body. 
Where is a ball and socket joint found? % 

What bones are united by sutures? 
What bones are united by cartilages? 
How are the bones bound to each other? 
Name four uses of the bones. 
Into how many groups are the bones divided? 
What is the skull? 

Point out on the Aid, the frontal bone, — the parietal — tem- 
poral — occipital. 
How many bones form the face? 
What two form the bridge of the nose? 
Where are the malar bones? 



18 ELEMENTARY PHYSIOLOGY. 

The upper maxillary? Lower maxillary? 

What is meant by the trunk? 

Where is the spinal column? 

Why is it built so strong? 

How is it made, elastic or springy? 

What benefit in this arrangement? 

How many vertebrae in the back-bone? 

How many of these are in the neck? 

How many have ribs attached to them? 

How many are in the loins? 

What bones make the frame of the chest? 

Are the ribs united directly to the sternum? 

Is the sternum as hard as other bones? 

What benefit in these arrangements? 

How is the lower part of the skeleton of the trunk shaped? 

W T hat is it called? 

What three bones come together at the shoulder? 

What two in the forearm? 

How many in the wrist? 

How many in the middle of the hand? 

In each finger? 

In each thumb? 

Which is the longest bone in the skeleton? 

What two bones in the lower leg? 

How many heel bones in each foot? 

Why is the foot arched instead of flat? 



THE MUSCULAR SYSTEM. 



MUSCLES. 

We have studied the framework or skeleton of the 
body. We have seen from the figure of it in the 
Anatomical Aid, how it resembles the framework of 
a house before it is weather-boarded and shingled. 
The plate of the body which is now before us pre- 
sents altogether a different view from that which we 
have been studying. We notice that it looks more 
like the full body, more like a house that is enclosed. 
The bones are here quite concealed by another 
division of organs — the muscular system. The 
word system in Physiology means the whole collec- 
tion of parts or organs of the body, which perform 
similar work or which work together for some com- 
mon purpose. We are already acquainted with the 
bony system. We will now study the muscular 
system. 

The muscles form the lean flesh of the 

Muscles body. The meat which we eat for food 

is chiefly muscle. We are all familiar 

with the dark red color of beef when it is 

(19) 



20 ELEMENTARY PHYSIOLOGY. 

raw. You have also undoubtedly noticed that the 
muscle or lean meat of pork is of a paler red, and 
the meat on the breast-bone of a chicken is quite 
white ; so muscle is not always red ; but it is gen- 
erally red, and the plate shows us that the muscles 
of the human body are of a quite red color. 

There are 527 muscles in your body. 
Number and Each one of these is made up of many 

Structure of ... ™ 

Muscles. strands or string-like fibers. These 

are laid side by side in the muscle, 
sometimes making quite a thick bundle. Each fiber 
of a muscle bundle is, however, separated from the 
rest by a very delicate substance. If you will take 
a piece of cooked meat, when it is cold, you can pull 
the muscles apart into strands, and these strands 
can be separated into many finer fibers or threads of 
muscle. While this is being done, you can observe 
the breaking and crackling of the very thin layer of 
matter which separates the fibers. The muscles 
differ from each other in shape. Some are spread 
out much like a fan. Others are quite circular in 
form, like this one (5) around the eye, or this (15) 
around the mouth. Some are quite long and of 
nearly even thickness. The largest muscle in the 
body is this (60), called the tailor muscle. It is 
nearly a yard long and does the work of crossing 
the legs. 

The ends of the muscles are attached to 
the bones by means of a hard white sub- 
stance or cord, which is called a tendon. These 



THE MUSCULAR SYSTEM. 21 

tendons are very strong. Besides binding the 
muscles very firmly at their ends to the bones, they 
are very usef al :n giving a graceful shape to many 
parts of the body. For instance, if these (39 and 
40) muscles of the forearm, which must have a con- 
nection with the fingers, were all continued as mus- 
cular bundles, through the wrist, hand and finger- 
joints, the hand would have a very clumsy figure. 
But these muscles reach out to the finger-joints by 
means of their tendons, and these tendons are 
neatly bound down, to run snugly along the bones, 
by means of ligaments, like this (45), so that the 
hand is really a very shapely organ. This (63) shows 
the tendon of this (62) muscle of the leg, and here 
(68) is the tendon of this (66) large muscle of the 
thigh. 

The muscles have been very appropriately 
the called "our servants," furnished us with 

" the house in which we live." They are 
indeed very faithful servants. It is their work to 
move, in many ways, the different parts of the body; 
or, as in walking, to move the body as a whole. 
There is no movement of any part of the body which 
is not produced by the action of one or more mus- 
cles. Every step we take, the slightest motion of a 
finger, the movement of the lips in speaking, the 
chest in breathing, or the eye in winking — all 
these movements are produced by the muscles. 
The rapidity with which these muscles work 
is quite astonishing. To be convinced of this, 



22 ELEMENTARY PHYSIOLOGY. 

we may observe the movements of the fingers 
of a skillful pianist or a rapid type-writer. To help 
you understand still better how very rapidly the 
muscles can act, you may remember that in say- 
ing the one word muscle, the mouth, tongue and 
voice organs must be pat, in succession, into four 
different shapes or positions, all of which is done by 
the proper muscles. We must not get the idea that 
only the bones are moved by the muscles. Many 
other parts of the body are moved by their action. 
For instance, the lips in whistling, the eye -lids in 
winking, the skin in wrinkling the forehead, or the 
heart in its ceaseless beating. When a dog pricks 
up his ears, or a horse drives off the flies by shak- 
ing his skin, it is done by the action of the muscles. 

There is another use which the muscles 
Language 

of the serve, which is very interesting. It may 

be called the language of the muscles, 
and it is remarkable how often they speak for us. 
A frown on the face is purely the work of the mus- 
cles; yet everybody understands its meaning. The 
same is true of a smile. You see two men at a dis- 
tance standing face to face and near together, with 
clenched fist and up-raised arm. You do not hear a 
word they say, but the action of their muscles, which 
you see, tells you how they feel. You pass near by 
a vicious horse, as he lays back his ears, or approach 
a dog whose hair on his neck is drawn up stiff and 
straight, you hear no sounds, but you understand 
the warning. It is the silent but expressive lan- 
guage of the muscles. 



THE MUSCULAR SYSTEM. 23 

_ „ a Some of the muscles of the body act 

Two Kinds J 

of Muscular only when they are directed to do so by 
the mind or the will. These are called 
voluntary muscles. Others act without being con- 
trolled by the will. These are called involuntary 
muscles. The muscles of the arm, for example, are 
voluntary muscles. The muscles which produce the 
action of the heart are involuntary. Some muscles 
may act either with or without the action of our will. 
For instance, the muscles which produce winking 
usually " wait for no thinking." But we may will to 
wink, and wink whenever we please. On the other 
hand, the will usually controls the action of the 
motion of the jaws. But sometimes, as in the case 
of a chill, these muscles produce chattering of the 
teeth rather contrary to the direction of the will. 
How the Motion is produced by the muscles, by 
muscles the contraction of the fibers. A muscle 
shortens more or less according to the 
degree of motion which it is to produce. The short- 
ening in length is caused by a swelling out of the 
muscles sideways. This swelling or bulging of a 
muscle can easily be perceived while it is contracted 
and pulling or holding the part which it moves. 
Grasp your arm between the elbow and shoulder 
firmly between your thumb and fingers. Now raise 
your forearm toward your shoulder; you feel the 
thickening of the muscle which raises your arm. 
This (34) is the muscle whose action you so plainly 
feel. It is called the biceps muscle of the arm. This 



24 ELEMENTARY PHYSIOLOGY. 

name means double-headed, and this muscle is so 
called because it has two upper tendons or starting 
places. Here (32) is the one, and here (33) is the 
other. The return of the muscle to its usual shape 
and length is called its relaxation. The relaxation 
of this (34) biceps must take place to permit the 
arm to straighten out; but, at the same time, some 
other muscle or muscles must contract to move it 
into the straight position. A muscle which bends a 
part is called a flexor. One which serves to 
straighten a part is called an extensor. 
. , . ^ Most of the muscles of the body are 

Antagonists, J 

or counter paired off in their work. That is, the 

Muscles. ■• p , -. t i , . 

motion oi a part produced by a certain 
muscle is reversed by the contraction of some other 
muscle. Such muscles are called antagonists, or 
counter muscles. Here again we refer to the chart 
for illustration. To raise the forearm, as w r e have 
seen, this (34) biceps must contract; but to straighten 
it out again requires the action of this muscle (36), 
the triceps. So the biceps and triceps are antag- 
onists. These muscles (43 and 44) bend the fingers, 
while these (51 and 52) straighten or extend them — 
another illustration of counter muscles. 

The names of the muscles are very 

Some Prominent ^ 

Muscles and long and difficult to remember. It 

would be unwise and unreasonable 
to ask you now to learn many of them. But by 
studying a few of the more prominent ones you will 
learn something about their uses, and also how their 



THE MUSCULAR SYSTEM. 25 

names are formed. This (1) muscle, which occu- 
pies a very prominent place, begins on the occipital 
or back bone of the head, and reaches forward to the 
skin of the forehead over the frontal bone. Its con- 
traction raises the eyebrows and wrinkles the forehead. 
It is called the occipito-frontalis. It takes its name 
from the parts which it connects. This (15) curious 
muscle, when it contracts, puckers the lips. Physi- 
ologists call it orbicularis oris. Orbicularis means 
circular, and oris means of the mouth. So this 
muscle is named from its shape and position. Here 
(51) is a muscle which bears the name extensor 
indicis, which means the straightener of the index 
finger, this being precisely the work which the 
muscle performs. This muscle (22) takes its name 
from its position under the clavicle or collar-bone. 
So it is called the sub-clavian muscle. We see that 
some muscles are named after the parts which they 
connect; some from their shape and position; some 
from the work which they do, and others from their 
location. So the many long and difficult names of 
the muscles wdiich you find on this plate (to which 
the figure seems to be pointing), and w T hich are so 
meaningless to you now, are really very expressive 
and full of meaning, and may, some day, wdien you 
are more advanced in your studies, become very 
interesting to you. 

The comfort of the body, its grace of 
of the form and the prompt activity of all its 

Muscles. p ar {- s dep en( i V ery largely on the healthy 



26 ELEMENTARY PHYSIOLOGY. 

and vigorous condition of all the muscles. To keep 
them all in that condition, each one mast be used 
without being abused. A muscle which is not used 
loses its power of contraction, becomes weak and 
flabby, and finally altogether useless. On the other 
hand, if a muscle is overworked, it loses its power. 
If you were to tie up your arm in a sling, or bind it 
down to your side for a long time, you would lose 
the use of it entirely. If you should swing your arm 
for a longtime, the muscles which produce its motion 
would cry out in painful protest against the abuse 
which they suffer ; and were you to disregard their 
protest, they would "strike" and refuse, positively, 
to do the bidding of your will. The effect of the 
vigorous exercise of the muscles without overtaxing 
them, is to make them firm and strong; the stout 
arm of a blacksmith, and the strong limbs of a foot- 
man illustrate this. The difference between the 
robust figure and good health of a sturdy country 
boy and the slender body and feeble strength of his 
young friend in the city, lies mostly in the difference 
in amount of their general muscular exercise. But 
we must be careful not to mistake a bulky body, or 
thickness of the limbs, as a sign of stoutness and 
strength of muscle. It is true, indeed, that as the 
muscles grow stronger they grow thicker, and conse- 
quently increase the size of the limbs and trunk of 
the body. But the effect of the fat of the body is 
often mistaken for an "abundance of muscle." 



THE MUSCULAR SYSTEM. 



27 



OUTLINE. 



THE MUSCLES. 



The lean flesh of the body. 
Color, red. Number, 527. 
Composed of many fibers. 
Shapes : long, fan-shaped, flat and circular. 
Bound to the bones by tendons. 
What? -{ Voluntary and involuntary. 
Have power of contraction. 
Swell out when they shorten. 
Antagonists produce counter motion. 
Flexors bend, extensors straighten. 
*. Are kept healthy by exercise. 

Where? -I Found distributed in all parts of the body. 

w JTo give motion to all parts of the body by the 
^ contraction and relaxation of their fibers. 

SUGGESTIONS TO THE TEACHER. 



In these lessons, whether you teach them by oral exercises 
or in recitation by the pupils, you can add much interest and 
practical instruction by bringing before your class illustrations 
of the real working of the parts or organs which are being 
studied. This can often be done very conveniently, and will 
contribute much to the pupils' knowledge of the functions or 
use of the organs (physiology), while the Anatomical Aid gives 
them a correct view of the structure (anatomy) of the parts. In 
studying the muscles, especially, such real examples of their 
work are very easily given. Name and point out on the plate 
a certain muscle. Make it serve your will as your pupils look 
on. Then let the class, in concert, join you in the perform- 
ance. Wrinkle the forehead, close the eyes, pucker the mouth, 
swell the cheeks, raise the arm, etc. This will make the 
information which is imparted " stick,' 7 because it is stored 
in the mind among the pleasures of memory. 

The " drum-stick " of a chicken — which some pupil may 
like to contribute — will, at this stage, furnish a very good object- 



28 ELEMENTARY PR YSIOLOGY. 

lesson. Show how the muscles are grouped about the upper 
part and gradually taper down to the bone. Below the muscle, 
lying along the bone, is a tendon. Separate the muscle. If 
the u drum-stick " has become cold, after having been cooked, 
you may hear the crackling of the delicate little sheaths which 
encase the fibers. When you have removed all the muscles, 
you have left two representatives of the bony system — the 
larger bone, the tibia, and the slender bone by its side, the 
fibula, corresponding, in position, to the same bones in the 
human body. 

TEST QUESTIONS. 

What part of the body do the muscles form? 

What is the usual color of the musc-es? 

How many muscles are in the body? 

What can you tell of the structure of a muscle? 

How do muscles differ in shape? 

What is the shape of the muscle which closes the eye? 

What and where is the longest muscle of the body? 

What is the use of the tendons? 

Can you explain how the tendons assist in giving a graceful 

shape to the body? 
What is the use of the muscles? 

What parts, besides the bones, are moved by the muscles? 
Can you give an illustration of the language of the muscles? 
What is meant by a voluntary muscle? 
What is an involuntary muscle? 
What is meant by the contraction of a muscle? 
What by relaxation? 

What is the difference between a flexor and extensor muscle? 
What are antagonists or counter muscles? 
How is a muscle affected by being unused? 
What is the result of too severe exercise? 
Is a bulky body always a strong body? 
What is likely to make the body bulky? 



THE NERVOUS SYSTEM. 



So far as we have now studied the body we have its 
framework and the muscles which are to give motion 
to its various parts. We have learned hoiv the mus- 
cles act, and now comes the question: What causes 
them to act as they do? We have learned of the 
obedience of the voluntary muscles to the will. But 
how does the mind or will direct them, when, how 
much, and how long to act? For the purpose of 
enabling the mind to control the action of the mus- 
cles, a very interesting system of organs is provided 
in the body, namely, the nervous system. This plate 
gives us an excellent view of it. 

The brain is, in many respects, the most 

Tlie Brain. 

important organ of the body. It occu- 
pies the loftiest chamber of the body house. [Raise 
the face section and refer to the brain on plate. ) 
Here the mind — the invisible tenant or occupant of 
the body — seems to form its purposes and send out 
its orders to its hundreds of servants stationed at as 
many points, between top and toe. Here, also, it 
receives its messages of intelligence from the body 

and from the outside world. These messages may 

(29) 



30 ELEMENTARY PHYSIOLOGY. 

bring it pleasure or pain; and they largely influence 
its decisions, its orders and its temper. 

The brain is an exceedingly soft and 

Structure. . . 

delicate organ. If: it were not enclosed 
in a triple sac and nicely fitted into its bony cham- 
ber it would fall apart from its own weight. It is 
composed of two kinds of substance, one of which is 
gray in color and the other white. The outer por- 
tion of the brain is composed of the gray matter. 
The white matter occupies the inside portion. 

The brain is surrounded by three coats 
Protection or membranes. The one lying next to 

to the Brain. ## . 

it is a delicate covering containing 
vessels which supply the brain with blood. This 
membrane takes its name from its purpose of careful 
protection; so it is called the pia mater — which 
means a tender mother. It lies v^ry close to ,the 
surface, stretching over the little hills and dipping 
down into the little valleys, with which the outside 
of the brain is covered. Next to the^pia mater lies 
a membrane so delicate that it was named after a 
spider's web — arachnoid. This membrane performs 
its work of protection by collecting from the blood a 
watery fluid to moisten the surface of the brain and 
prevent any possible friction. The outer coat is quite 
tough and substantial: so it is called the dura mater, 
or hard mother. It lies close to the inside surface 
of the skull bones. Now we can see how the brain 
is protected, for instance, against a blow on the head. 
The effect of such a blow would be diminished, first, by 



THE NERVOUS SYSTEM. 31 

the hair, then by the skin and muscles overlying the 
skull, then by the bone, next by the hard coat, then 
by the water coat, and finally by the soft coat — mak- 
ing no less, than a half-dozen successive defenses 
against harm to the castle of the mind. 

The brain is divided into two parts, one 
Divisions of t which is much j than the other 

the Brain. © 

These parts are shown here, in this 
section which represents the head as divided from 
top to bottom, close behind the ears. We will now 
refer to the manikin of the head, where we will get 
a very clear view of the size and position of these 
brain parts. [Fourth sectioji of the head.) This 
(74) large upper brain is called the cerebrum. It 
fills the whole front and upper part of the brain-box. 
The small brain (75) is called the cerebellum. 
Notice that it lies behind and below the large divi- 
sion of the brain. When this small brain is cut 
through, its inner structure has this tree-like appear- 
ance (shown on plate), called the arbor vitce. 

Both the cerebrum and cerebellum 

Hemispheres. . _ . 

are divided into two parts, called the 
right and left hemispheres. The lower parts of the 
two hemispheres are united by several small mys- 
terious-looking organs, whose particular use has 
been a puzzle even to many wise heads, but which 
certainly have some special part to perform in the 
wonderful control of the mind over the body. The 
last section of the head {turn to it), which repre- 
sents it as cut through from front to back, in the 



32 ELEMENTARY PHYSIOLOGY. 

middle, shows us the right hemisphere of both the 
larger and the smaller brain. The red vessels, in the 
figure, are blood-vessels which bring large quantities 
of the purest blood iir the body to the brain, for a 
purpose of which we shall learn hereafter. 

From many observations and experi- 
the^erebrum m ents which have been made by 
physiologists, it has been learned 
that the large brain is the thinking organ of the 
mind. It is here that impressions received from 
the outside world are translated into thought and 
feeling. Here the purposes of the w r ill are formed, 
and from here all orders for the action of the volun- 
tary muscles are issued. 

The work of the small brain seems to 
cerebellum, ^e to regulate the muscular movements 
which are directed to be made by the 
large brain. It has been discovered that when the 
cerebellum is injured, a person can not balance 
the body, as is required even in standing and much 
more in walking. A bird whose small brain is 
seriously injured or removed, can move its wings 
and its legs, but it can neither fly nor walk. 

The nervous matter of the brain is con- 
Cord. Pma tinued down through the back, passing 

through openings in the bones of the 
spinal column. This is called the spinal cord. Here 
{131, last section of the head) is where the spinal 
cord begins. This (124) upper part of the cord 
(medulla oblongata) is a very important part of the 



THE NERVOUS SYSTEM. 33 

nervous system, for the reason that it seems to have 
control of some of the most vital operations of the 
body. When it is injured, the breathing muscles 
fail to act, .which, of course, neans instant death. 
Here (150) we see the spinal cord continued down- 
ward. Now we will turn again to the nervous plate of 
the Aid, where the whole of this great nervous 
cord is shown with its numerous branches of nerves. 
The nerves are composed of the same 
substance as the brain. They are sil- 
very threads which branch out from the brain and 
spinal cord and are distributed to all parts of the 
body. Twelve pairs pass out through openings of 
the cranium. These are called cranial nerves. 
Thirty-one pairs pass out from the spinal cord 
through openings of the back-bone, as shown on the 
plate. These are called spinal nerves. The cranial 
nerves go to the eye, ear, nose, tongue and other 
important organs. The spinal nerves go to the 
arms, trunk and legs. 

Besides the nerves which branch out from the 
brain and spinal cord, there is, on each side of the 
back-bone, a chain of nerve centers — little bits of 
brains, as it were — running down through the body. 
From these small nerve knots, delicate nerves run out, 
some to the heart, lungs and stomach, and others to 
the blood-vessels and to the cranial and spinal 
nerves. So all the important organs of the body are, 
in this way, connected with each other and with the 
brain. This figure [The Sympathetic System) shows, 



34 ELEMENTARY PHYSIOLOGY. 

beautifully, this wonderful nervous connection. The 
interesting object of this arrangement — which is 
called the sympathetic nervous system — we shall 
soon learn. 

There are three kinds of nervous action. 
Action! 8 We will first consider the relation between 

mind, brain and nerve. The nervous 
system is very much like a telegraph system. The 
mind has been called the operator, the brain and 
spinal cord the sending or receiving offices or 
instruments, and the nerves the wires or lines 
running to all parts of the body. The comparison 
is very apt, indeed. One set of nerves runs from 
the brain or spinal cord to the muscles, so that every 
muscular fiber is in direct communication with head- 
quarters. Now, wherever a muscle is to act, every 
fiber of it, in some mysterious way, gets a message 
over its nerve line, from the nervous capital, 
directing it precisely how much to contract or r§lax. 
For example, you make up your mind to close your 
eyes. The order is sent ont over the nerve lines 
which go to the fibers of the circular muscle which 
we have found to lie around the eye, and promptly 
the eyelids close. The nerves which carry messages 
to the muscles are called nerves of motion. Another 
set of nerves are called nerves of feeling. They 
carry impressions from the body to the brain. These 
nerves are distributed so thickly near the surface of 
the body, in the skin, that it would be almost impos- 
sible to find a point on the body where the prick of 



THE NERVOUS SYSTEM. 35 

a pin would not be felt. If you touch your body on 
its skin surface anywhere, even with the fine point 
of a needle, you are sure to disturb one or more of 
the nerves of feeling. Quicker than thought they 
report the impression, according to the degree of its 
severity, to the brain, which, if the situation at the 
surface demands it, will promptly return an order, 
over the nerves of motion, to the muscles of the 
endangered part, to do their best to get it out of the 
way of harm. For instance, a mosquito may alight 
on your forehead so lightly as to make no 
impression on your nerves of feeling, and, con- 
sequently, you are not aware of it. But now he 
punctures the skin and touches a nerve with his 
wonderful little stiletto. The news of his attack has 
been received by the brain, and an order sent back 
for defense and protection. Quicker than thought 
your hand has come up and routed or crushed the 
little assassin. 

But the impressions which the nerves of feeling 
carry to the brain and mind are not all alarming or 
painful. Many of them are impressions of comfort 
or pleasure. A gentle breeze fans your body on a 
hot summer day. Hundreds of nerves are telling 
it to the mind, which enjoys it as a pleasure. Light 
impresses the nerve of sight, and beautiful views 
of form and color are spread before the mind. 
Sound excites the nerve of hearing and the charms 
of music are enjoyed. Invisible particles from a 
rose come in contact with the nerve of smell and we 
are delighted with the fragrance of the flower. 



36 ELEMENTARY PHYSIOLOGY. 

If all the muscles were voluntary muscles, 
Xervons that is, if no movement of the organs of 

the body could be made without a special 
order from the mind, the continuance and enjoyment 
of life would be impossible. Every breath, every 
heart* beat, and many other operations of organs 
which can scarcely be dispensed with for even a few 
moments, would need to be constantly thought of 
and directed. Fortunately, the mind, and even the 
brain, is relieved from the ordinary control of the 
operations of organs upon whose regular and con- 
stant action our life depends. So the heart goes on 
beating, the lungs continue breathing and the stom- 
ach keeps on working, while the mind rests and the 
brain sleeps. Let us see how this is done. 

The spinal cord may be regarded as a continua- 
tion of the brain. It is composed of the same two 
kinds of matter — white and gray. We may also look 
upon the spinal cord as a deputy brain. A deputy 
is appointed as a substitute for another, and empow- 
ered to act for him. An officer may have more duties 
to perform than he can personally attend to. So an 
assistant is given him, who is entrusted with certain 
lines of work for which he is held responsible. When 
serious questions or difficulties arise in the assist- 
ant's department of work, he appeals for special 
advice to the chief officer. So in the body, while the 
brain executes the orders of the mind, and controls 
the voluntary operations and movements of the body, 
the spinal cord is entrusted with the control of the 



THE NERVOUS SYSTEM. 37 

involuntary muscles which perform the work of the 
heart, lungs, stomach and other vital organs, except 
in cases of emergency. For example, when food 
comes into the stomach, certain movements of the 
walls of that organ are necessary. So the food makes 
an impression on the nerves which report its pres- 
ence, not to the brain or to the mind, as a sensation, 
but to the origin center of those nerves, in the spinal 
cord. Here the cord exercises its authority and 
returns (reflects) an order over motor nerves to the 
muscles of the stomach to perform the needed 
service. 

In the same way, the presence of impure air or 
the absence of air in the lungs causes impressions 
which are carried to the cord, which returns orders 
for the action of the breathing-out or breathing-in 
muscles, as the case may be. All these performances 
go on steadily, whether we are awake or asleep. 
But when an emergency arises, as, for instance, if 
the muscles of the chest are strongly resisted in their 
efforts to expand it, by outside compression, the 
news of the trouble is carried beyond the nerve cen- 
ters of the cord up to the brain, where the mind 
quickly grasps the situation and promptly issues 
orders for the best possible measures of relief. A 
familiar illustration of reflex action is found in the 
flapping of a fowl whose head has been cut off. Its 
muscles which produce its violent motions are not in 
connection with the brain, and can not be controlled 
by it. Each fall to the ground produces an impres- 



38 ELEMENTARY PHYSIOLOGY. 

sion which starts from the cord a message for the 
repetition of these muscular movements. Even 
when it seems to have settled down quietly, if you 
touch its body the movements will be renewed. 

^ A . We have seen how the sympathetic 

Sympathetic J L 

xervous nerves connect important organs with 

each other and each with the brain. So 
if one organ suffers, the others suffer more or less 
with it. When the stomach is distressed, the head 
aches. When the heart's action is excited, the 
stomach is affected. When the brain is impressed 
with the mind's sense of shame or modesty, the little 
blood-vessels in the skin of the cheeks swell out and 
are more than usually filled with blood, and we call 
this delicate expression of their sympathy, blushing. 

We would naturally suppose that organs 
the Nervous so delicately constructed, and yet so 

prominent in the operations of the body 
as those of the nervous system, w 7 ould need the most 
proper care to prevent their derangement or injury. 
And so it is. The brain needs especial care. It 
needs rest at proper intervals ; not only from severe 
application, but the complete rest of sleep. An 
overworked brain is a diseased brain. On the other 
hand, the brain must have a proper amount of exer- 
cise to keep it in vigor. Besides healthy and varied 
exercise, the brain needs pure blood regularly and in 
proper quantities. Too much or too little blood will 
paralyze it. Hence its dependence on the proper 
action of the blood-circulating system. Impure 



THE NERVOUS SYSTEM, 39 

blood will weaken its action. Hence its dependence 
on the blood-purifying system. 

Severe excitement of the mind or long continued 
anxiety cripple the work of the brain, and finally 
result in insanity. A cheerful state of the mind is 
favorable to healthy nerves and long life. Conse- 
quently, all proper enjoyments, as the delights of 
music, pleasant changes of scenery, varied means of 
recreation and social pleasures, are like tonics to the 
nervous system first, and through it to the whole body. 

There is no system of the body that is more 
severely outraged by the habit of drink and the use 
of narcotics than the nervous system. But this sub- 
ject is so very important that it will be fully explained 
in a special chapter, after we are still better 
acquainted with the structure of the body. 

OUTLINE. 

THE NERVOUS SYSTEM. 

r Consists of brain, spinal cord and nerves. 
Very soft and delicate in structure. 
Composed of white and gray matter. 
The large brain called the cerebrum. 
The smaller brain the cerebellum. 
Right and left halves of brain — called hemispheres. 
Nerves of two kinds, nerves of sensation or im- 
pression and nerves of motion. 

Brain enclosed in cranium. 

Spinal cord extends from base of brain through 

the spinal canal of back- bone. 
Nerves branch out from the brain, spinal cord and 

the sympathetic nerve knots, and are distributed 

to all parts of the body. 



What? < 



Where? i 



Why? 



40 ELEMENTARY PHYSIOLOGY. 

To serve the mind in directing the voluntary 
movements of the body. 

To control, by reflex action, the involuntary mus- 
cles. 

To bring to the mind, from the body and from the 
outside world, impressions producing the sensa- 
tions or feeling of touch, taste, light, sound, 
smell, pain or pleasure. 

QUESTIONS. 

What are the organs of the nervous system? 

What position in the body does the brain occupy? 

Whose special instrument does the brain seem to be? 

What can you say of the brain's structure? 

What difference in the color of its substance? 

Describe how the brain is protected. 

What is the cerebrum? 

What is the cerebellum? 

What is the arbor vitse? 

What is meant by the hemispheres of the brain? 

What can you tell of the work of the cerebrum? 

What seems to be the use of the cerebellum? 

Where is the spinal cord? 

What is its upper part called? 

What makes this part so very important? 

What are the nerves? 

From where do they start? 

Where do they go? 

How many pairs pass out from the skull? 

What are these nerves called? 

How many pairs branch off from the spinal cord? 

What are these called? 

Where do the cranial nerves chiefly go? 

To what part are the spinal nerves chiefly sent? 

What can you tell of the sympathetic nerves? 

To what have we compared the nervous system? 

Tell what you can of the comparison. 

Do all the nerves perform the same kind of work? 

Explain what is meant by the nerves of motion. 



THE SPECIAL SENSES. 41 

What is meant by the nerves of feeling? 

Does the mind attend to all the movements of the body? 

If not, will you explain your answer? 

What kind of muscles are controlled by the nervous system 

independently of the mind? 
What is such nervous action called? 
Can you give an example of reflex action? 
What is sympathetic nervous action? 
Can you give an example of it? 
Why does the nervous system need special care? 
What kind of exercise is needed by the brain? 
By what habits are these organs especially injured? 



THE SPECIAL SENSES. 



All the sensory nerves except four, 

IVcrvcs of 

Common Sen- are nerves of common sensation. 

sation. They are distributed everywhere 

throughout the body. They need no special organs 
to enable them to receive impressions. Near the 
surface of the body or in the skin, they end in little 
folds or loops called papillce. All the nerves of the 
sense of touch are nerves of common sensation. 

There are four nerves of special sensa- 

STerves of L 

Special sen- tion. These are the nerves of sight, 
hearing, smell and taste. Each of these 
nerves has a special organ without which no impres- 
sion can be received to be carried to the brain. 
These organs are very delicate and wonderful struc- 
tures. They are really special instruments of the 
nervous system. 



42 ELEMENTARY PHYSIOLOGY. 

THE EYE. 

(Third Section of Head Manikin.) 

This (46) is one of the nerves of special sensa- 
tion — the optic nerve, or nerve of sight. It connects 
with and terminates in the eye. This nerve is 
impressible only by light. Without the eye, the light 
would not impress it. The eye is an instrument to 
gather the light which is reflected to it from objects 
and to bring it to bear on the optic nerve in such a 
way that an impression is made and carried to the 
brain, where the mind receives the impression as a 
picture of the objects from which the light came. 
How all this is done is very mysterious. But the 
organs which are concerned in the process can be 
easily examined and studied. 

Let us notice, first, that the eye is 
The Eye!° n of lodged in a deep socket of the bones 

of the head. Besides this feature of 
protection, there is placed behind and around the 
eye, quite a layer of fat, so that, even if the eye is 
struck, the force of the stroke is very much lessened 
by this fatty cushion. In front, it is guarded by the 
eyelids, eyebrows and eyelashes. The eyelids serve 
as a curtain. The eyebrows prevent the perspiration 
from running down from the forehead upon the lids. 
The eyelashes prevent dust from entering between 
the eyelids. 

(Manikin of the Eye.) 

Turning aside this outer section which 

ratus. APPa " represents the natural open eye, we see 

a gland lying in the outer corner above 



THE SPECIAL SENSES. 43 

the eye. This is called the lachrymal or tear gland. 
It secretes from the blood a watery fluid which it 
pours out upon the eyeball. By the act of winking 
the eyeball is entirely bathed by this fluid, which 
after it has flowed over the eye, collects in a little 
lake at the inner angle, from whence it is drained by 
two little channels (2) into the tear duct (1) which 
communicates with the nose. Shedding tears is 
simply an overflow of this eye-bathing fluid, when 
it is secreted in unusual quantity. At such times 
the little channels cannot carry it away sufficiently 
rapid ; so it flows over upon the cheeks. This unu- 
sual activity of the tear gland may be produced by 
certain states of the mind, as sorrow or great joy; 
or by certain diseased conditions of the parts about 
the eye, as an inflammation or a severe cold. 

The eyeball has three coats. The outer 

The White J 

coat of the coat, or white of the eye, is called the 
Eyeball. sclerotic. It is a strong, tough mem- 

brane which forms quite a substantial case into 
which the cornea is set in front, like the glass or 
crystal of a watch. The sclerotic coat is not sensi- 
tive; that is, it has no nerves of feeling. But it is 
covered, in front, with a very delicate membrane 
w r hich contains very fine blood-vessels and nerves. 
When these little blood-vessels become swollen with 
an unusual amount of blood, the eye is said to be 
"bloodshot;" and when a cinder or dust grain 
lodges on the eye and makes an impression on the 
delicate nerves of this fine protecting veil, the sen- 



44 ELEMENTARY PHYSIOLOGY. 

sation is very painful. No light passes through the 
sclerotic coat; but the cornea is very transparent. 

Next to the tough outside white coat 
The Black u the c / zoro ^ This is a soft black 

Coat. 

membrane. It prevents the reflection 
of strong light from the inner surface of the eyeball, 
and this serves an important part in making the sight 
sharp and clear. The front part of the choroid coat 
is arranged like a circular curtain. This is called 
the iris. This is what gives the eye its so-called 
color. The difference between a black eye and a 
blue eye is, that the cells of the iris of the one have 
a black coloring matter in them, while the cells of 
the iris of the other contain blue coloring matter. 
In the center of the iris is a circular opening called 
the pupil which you can see by looking directly into 
the eye of another person who stands close before you. 
Through this little circular window, surrounded by 
the curtains of the iris, the light must pass on its 
way to the back inner part of the eyeball. The 
amount of light which passes through the pupil is 
regulated by an interesting action of the iris. When 
the light is strong, the little muscles which are 
threaded through the curtain produce the effect of 
making the pupil smaller so as to pass less light. 
When w r e go from a light place into a dark, these 
same muscles bring about an opposite effect, that is, 
the pupil is made larger so as to admit more rays. 
This adjustment of the curtain of the eye is not in- 
stantly done. It requires some time. This you can 



THE SPECIAL SENSES. 45 

easily observe. For, in going from the dark into a 
very light room you can not see well until the change 
in the size of the pupil-window of your eye has been 
made. So, also, when going from a bright room into 
a dark place, at first it seems to be " pitch dark ;" 
but, by and by, when your eye is adjusted to the 
change, you may be surprised to find that it is not 
so dark after all. 

The third or inner coat of the eye is 

The Kervoiu ^ reKfUk Thig lies only oyer the back 
Coat J 

part of the inner (eyeball. It is really 
the end of the optic nerve, or nerve of sight, spread 
out to receive the impression of the light in the eye. 
By turning to the last section of this eye-manikin, 
we find this clearly represented. Here is a small 
part of the white coat of the back part of the eye- 
ball. It show r s the opening (23) where the optic 
nerve enters through this coat. Turning down the 
section which lies just before this, we see the open- 
ing (21) for the nerve through (22) the choroid coat. 
Turning forward another section we come to the retina 
(15) into which the nerve is expanded and over 
which the blood-vessels (19, 20) which enter the 
eyeball with the nerve, are distributed. The retina 
is an exceedingly delicate nervous screen on which 
the action of the different parts of the eye makes a 
picture of the object we look at. How this picture 
is carried by the nerve to the brain and there grasped 
or perceived by the mind we do not understand. 



46 ELEMENTARY PHYSIOLOGY. 



(Sense of Sight.) 



Between the cornea and the iris, in the 

of'thf Eye™ fr ° nt P art ° f the e ^ e ' iS a Water y fluid 

called the aqueous humor (18). Back 
of the iris lies the crystalline lens (23). This is a 
beautiful gem-like little body — as clear as a crystal. 
Back of the lens, and between it and the retina, the 
eyeball is filled with another clear jelly-like sub- 
stance called the vitreous humor (25). The effect 
of these three humors which are contained in the 
eye, and especially the effect of the lens, is to produce 
the image of things on the retina, as has already 
been mentioned. 

(Third Section of Eye Manikin.) 

These muscles, which are shown to be attached to 
the outer sclerotic coat, produce some of the prin- 
cipal movements of the eye — upward, downward, in- 
ward and outward. By the way, we also mention 
that the action of the muscles of the iris in regulat- 
ing the size of the pupil, is an interesting example of 
what we have already learned to name reflex nervous 
action. 

THE EAR. 

The nerve of special sensation which 
T ] 1 ^ J^ er 7 e goes from the brain to the ear is called 

of Hearing. ° 

the auditory nerve. As the nerve of 
sight is sensitive only to light, this is sensitive only 
to sound. The ear is an instrument to collect sounds 
and bring them to bear on the auditory nerve in 



THE SPECIAL SENSES. 47 

such a way that an impression is made and carried 
to the brain to be recognized by the mind. 

The ear is divided into the outer, middle 
outer Ear. and inner ear. Tne outer ear has a 

more or less cartilaginous frame. This 
allows motion, and, at the same time, keeps it in 
shape and position. It has also a few small muscles. 
But in the human ear these are nearly altogether 
useless, since men do not move or flop their ears. 
In animals which move their ears in various ways, 
these muscles are quite well developed. 

(Sense of Hearing.) 

From the outer ear (1) a tube, a little 
The Middle over au j^k long, called the auditory 

canal (2), leads in to the middle ear, 
where it is closed by a membrane called the mern- 
brana tympani, which means the membrane of the 
tympanum or drum (3). The middle ear is often 
called the "ear-drum," and the membrane just men- 
tioned may be called the "drum-head,'' for it does, 
indeed, act very much like the head of a drum. 
Between this membrane of the drum and its inner, 
opposite side or end, there is stretched a very curious 
little suspension bridge of four small bones. The 
first of these is attached to the drum-head, and from 
its shape like a hammer is called the malleus (4). 
The next is called the incus, because it is shaped 
like an anvil (7). The third is a very small pebble 
of a bone called the orbicular or round bone (10). It 



48 ELEMENTARY PHYSIOLOGY. 

is followed by the stapes or stirrup bone (12), the 
last span in the little bridge. This rests against a 
small window-like membrane which is stretched over 
an opening in the inner side of the drum. At the 
bottom of the ear-drum or middle ear is an opening 
into a tube which leads from the ear to the throat 
This is called the Eustachian tube. Its object is to 
supply the ear-drum with air, for without air inside 
to balance the pressure of the air on the outside 
of the drum-head, the action of the latter would be 
very imperfect and our hearing, in consequence, very 
dull. We frequently experience the truth of this 
statement; for whenever the Eustachian tube be- 
comes clogged, as in the case of a very bad cold, 
our hearing is very much impaired. 

The inner ear is carefully hidden in a 
The inner k n w place in the solid bone. In that 

Ear. * 

part of it which lies next to the mid- 
dle ear, is a little hall-way, or vestibule, about as 
large as a grain of wheat. This leads, on one side, 
into the arched or semi-circular hall-ways which are 
called the semi-circular canals (13, 14, 15). On 
the other side the vestibule opens into the cochlea 
(16, 17), which is shaped like a snail shell or a tiny 
winding stair. Here the auditory nerve, or nerve 
of hearing, takes up the impression of a sound and 
transmits it to the brain. 

All sounds are produced by the vibra- 
Hear. tions of bodies. To make this plainer, 

when a bell is struck its particles are 



THE SPECIAL SENSES. 49 

thrown into a violent trembling. By these trem- 
blings or vibrations of the material of the bell the 
air is thrown into a wave-like motion all around it. 
When these trembling air waves reach the ear, the 
sensation of sound is produced and we say we hear 
the bell. When a person speaks to us the voice 
chords in his throat are set into rapid vibration. 
These vibrations produce waves of sound in the air; 
the air carries these waves to the ear, where, passing 
in through the auditory canal they tremblingly beat 
upon the drum-head; this carries the sounds to the 
bridge of little bones. Having passed over these, 
it enters the vestibule, then vibrates into the semi- 
circular canals and rebounds into the cochlea, where, 
as already stated, it is taken up by the nerve and 
carried to the brain where the mind interprets it as 
the voice and the language of the speaker. 

THE SENSE OF SMELL. 

The organ of smell is the nose and its cavities. 
The nerve of smell is called the olfactory nerve. 
This nerve is spread out in many branches over the 
delicate mucous membrane which lines the inside of 
the nose. To make the surface on which the nerve 
of smell is distributed as large as possible, there is 
set into the nostrils, against the outer walls, a pair 
of scroll-like bones. These are the turbinated bones 
of the face. Over their winding surfaces, covered 
with the mucous lining, the nerve of smell is spread. 
The two small nasal bones unite the nose to the 



50 ELEMENTARY PHYSIOLOGY. 

skull and keep it in shape. The lower part of the 
nose is shaped by a frame of cartilage, the advan- 
tage of which over a nose-frame of solid bone you 
can readily see. 

Things which have an odor, or smell, 

How We 5 ' ' 

Perceive give out little particles of matter, alto- 

gether invisible. As these float in the 
air, they are drawn into the breathing passages of 
the nose and mouth at every breath. Of course 
those which pass with the air into the mouth can 
make no impression of smell, for there are no nerves 
there which are affected by odors. But those which 
.pass into the nostrils strike upon the olfactory nerve 
branches which, as we have seen, have their special 
location there. The mind, receiving these impres- 
sions, recognizes the odor, which may be feeble or 
strong, agreeable or very unpleasant. 

The sense of smell affords us protection in two 
important ways. Its organ, the nose, is set at the 
very gates of entrance of the air we breathe and the 
food we eat. So when the air is filled with putrid 
or offensive invisible matter, which, of course, would 
make it unfit to breathe, we are cautioned by the 
sense of smell, and instinctively turn away and seek 
a purer air to breathe. Likewise, we are often 
warned, just in time, against putting into the mouth, 
as food, substances whose odor betrays their unfit- 
ness to be eaten. Fortunately it is so provided in 
nature that poisonous and other harmful substances 



THE SPECIAL SESNES. 51 

have generally a strong and peculiar smell, although 
this is by no means always the case. 

THE SENSE OF TASTE. 

The special nerves of taste have their 
The Tongue, loop-like endings chiefly in the tongue, 

which is, consequently, usually spoken 
of as the organ of taste. But these papillae, or end 
expansions of the nerve of taste are also distributed 
over the walls of the back part of the mouth. On 
account of the numerous little folds of nerve endings 
on the tongue, this organ has quite a velvety appear- 
ance. Besides serving as the chief organ of the 
sense of taste, the tongue also aids in the chewing 
of the food and in producing the sounds of speech. 

When substances which have a taste come 
How We . . 

Perceive m contact wath the papillae or nerve loops 

Taste. Q j! ^ e tongue, the impression is at once 

carried to the brain and mind. In order that 
such an impression can be made the substance 
to be tasted must be in a dissolved state. 
No dry or solid substance can be tasted. So 
the mouth is kept moist, and, as w x e shall learn 
later, during the process of eating, a large quantity 
of saliva is thrown into the mouth. This dis- 
solves at least a portion of the food or substance 
which is in the mouth, so that its taste is well per- 
ceived. When the mouth is dry from disease, or 
from great thirst, food has but little taste and is 
very unpalatable. So when the nerves of the tongue 



52 



ELEMENTARY PHYSIOLOGY. 



are covered with a strange coat, as iu disease, our 
food does not taste natural. 



WHAT , 



WHEKE? 



i 



WHY? 



OUTLINE, 

OKGANS OF THE SPECIAL SENSES. 

f Eye — the organ of sight. 
! Ear — the organ of hearing. 



i Nose— the organ of smell. 
(_ Tongue — the organ of taste. 
f Eye — under arch of frontal bone. 
! Ear — in hollow of temporal bone. 
i Nose — at entrance of air and food passages. 
^ Tongue— lies on the floor of the mouth. 
Eye — to collect rays of light from objects and pro- 
duce a picture or image of such objects on the 
expansion of the nerve of sight. 
Ear — to collect sound waves and convey them to 

the nerve of hearing. 
Nose — to bring odorous matter in contact with the 

nerve of smell. 
Tongue— to bring substances having taste in con- 
tact with the nerve of taste. 



QUESTIONS. 

Where are the nerves of common sensation distributed ? 

How many nerves of special sensation are there ? 

Can these nerves receive impressions directly ? 

What is the special instrument of the nerve of sight'? 

What is the proper name of the nerve of sight ? 

By what only is it impressible ? 

What is the use of the eye ? 

How is the eye protected by its position ? 

What other means of protection are furnished it ? 

What is the use of the lachrymal or tear gland ? 

Where is this gland situated ? 

After bathing the eye, how is that fluid drained away ? 

What is meant by "shedding tears" ? 

What conditions of mind and body may cause this 



THE SPECIAL SENSES. 53 

How many coats has the eyeball ? 

What is the nature of the outer coat ? 

What is the cornea ? 

Is the white coat of the eye sensitive ? 

How do you account for the pain felt when a cinder lodges 

on the eye ? 
What is meant by the eye being " bloodshot " ? 
Does light enter the eye through the white coat ? 
Through what does it enter ? 
What is the color of the middle or choroid coat ? 
What purpose does it serve in the eyeball ? 
Where and what is the iris ? 
What gives the eye its color ? 
What is the pupil ? 

How is the pupil regulated to admit more or less light ? 
Where and what is the retina ? 

What is formed by the eye on the screen of the retina ? 
What humor lies between the cornea and iris ? 
Where and what is the crystalline lens ? 
What humor occupies the back part of the eye ? 
Which of these parts is most effective in collecting the light 

on the retina ? 



What is the nerve of hearing called ? 
By what only is it impressible ? 
What is the work of the ear ? 
Into what parts is the ear divided ? 
What tube leads from the outer ear to the " drum " ? 
Describe the ear drum. 
What is the use of the Eustachian tube ? 
What are the parts of the inner ear ? 
By what are all sounds produced ? 

Describe the course of sound-waves from a sounding body 
through the ear to the nerve of hearing. 



What is the organ of the sense of smell ? 

What is the name of the nerve of smell ? 

To what is this nerve sensitive ? 

Against what does the nerve of smell afford us protection. 



54 ELEMENTARY PHYSIOLOGY. 

Where are the extremities of the nerve of taste located ? 

What gives the tongue its velvety appearance ? 

Why are dry or solid substances tasteless ? 

What provision is made to make food more perceptible to 

the taste ? 
Why does food have no taste to us when we are sick ? 



THE CIRCULATORY SYSTEM. 



Besides the material which the body needs for its 
growth, during twenty years or more, it is constantly 
exposed to wear and tear, and, consequently, it must 
be supplied continually with material for repair. It 
is impossible altogether to avoid the wearing out of 
parts of the body. Some of the muscles, like those 
of the heart, for example, are on constant duty. 
Every contraction of a muscle destroys a part of its 
fiber. The nervous system is also constantly suffer- 
ing wear. The slightest effort of body or mind pro- 
duces damage which must be made good to maintain 
our strength. The simplest thought which occupies 
the mind lays a tax on the structure of the brain. 
Either a wink or a whisper destroys muscular fibers. 
If even these gentle movements are wear'ng, how 
great must be the destruction throughout the body ? 
by labor which exercises vigorously the brain and 
many muscles. 

So a system of organs is provided in the body, 
whose work it is to carry to all parts a supply of 



THE CIRCULATORY SYSTEM. 55 

material as may be needed for building or repairing. 
This is the circulatory system. The blood — a bright 
red fluid with which we are all familiar — floats the 
building material through the channels and reser- 
voirs of the circulatory system, As the building of 
a house requires many kinds of material, such as 
wood, stone, iron, glass, lime, sand and putty, so the 
structure of the body calls for materials suitable for 
bone, muscle, nerve, hair, nails, and so on. All this 
variety of material is carried by the blood in its 
ceaseless rounds through the body. 

or ans of tiie ^ ie or g ans an d vessels of this system 
circulatory are the heart, the arteries, the veins, 
and the capillaries. The plate before 
us shows the heart in its position, and gives us a very 
good idea of the manner in which the arteries and 
veins run to and from every part of the body. The 
figures of the right arm and right leg are so drawn 
by the artist as to show us chiefly the veins of these 
limbs, while the figures of the left arm and left leg 
show chiefly the arteries. 

The heart lies near the center of the 

The Heart. 

chest, a little to the left of the middle 
line. A man's heart is about as large as his fist. It 
is a very strong muscular pump or engine and does an 
enormous amount of very important work, as we shall 
soon see. It has four chambers — two on each side. 
The upper chamber of the right side of the heart is 
called the right auricle (U) ; below this (W) is the 



56 ELEMENTARY PHYSIOLOGY. 

right ventricle. The left auricle (V) forms the 
upper chamber, and the left ventricle (X) the lower 
chamber of the left side of the heart. The upper 
and lower chambers — that is, the auricles and ventri- 
cles — are separated by valves, whose important use 
we will learn when we trace the course of the blood 
through the heart. 

The arteries are the vessels which 

r rhe A-rteries 

carry the blood in its course from 
the heart. All the arteries which distribute bright 
or pure blood from the heart for the nourishment of 
the body, are represented by red vessels on the plate. 
This large artery — the pulmonary artery (16) — 
carries dark or impure blood ; so it is shown in blue. 
Of course the arteries near the heart are very much 
larger blood-channels than those farther out, where 
they divide as you see, into very many branches. 

The veins are the vessels which gather 
up the blood from all parts of the body 
and carry it to the heart. All the veins which bring 
dark, impure blood to the heart are represented by 
blue vessels in the figure. This (31) large vein — 
the pulmonary vein — carries pure blood; so it is 
shown in red. The veins near the heart are very 
much larger than those which are farther away. 
There are valves in the veins to prevent the blood 
from flowing or setting back in a wrong direction. 

The capillaries are very fine tubes 

The Capillaries. ,. ,, , . .,, ., 

connecting the arteries with the 



THE CIRCULATORY SYSTEM. 57 

veins. Their name comes from a Latin word which 
means a hair. It is difficult to imagine how numer- 
ous these little capillary blood-vessels are, and bow 
well they are distributed to all parts of the body. 
You could scarcely prick your skin with a needle 
anywhere without bringing some blood to the sur- 
face ; you are sure to pierce some capillary and cause 
it to leak. 

In the capillaries are the landing 

Blood Change r . ° 

in the places where the little cargoes of 

capillaries. building material, which have been 
floated from the port of the heart through the arte- 
rial rivers, are unloaded and distributed to the thou- 
sands of little working cells, which are everywhere 
busy in building or repairing the body. At some 
places material for muscle is unloaded; at others 
material for bone, nerve or finger nail is wanted. In 
exchange for this new material which the capillaries 
distribute to the body, they take back from the body 
the material which has become old, worn out, and 
unfit for use. The consequence is that the blood 
which has come from the arteries into the capillaries 
red and pure, leaves them and gathers in the veins, 
dark and impure. It would be altogether unfit to 
make another round through the body without being 
purified; so the capillaries deliver it to the veins, 
and these carry it to the heart, which drives it to the 
lungs — one of the organs of another system — where 
its worn-out matter is unloaded, and it is again made 
fit to feed the body. 



58 ELEMENTARY PHYSIOLOGY. 

We will now trace and learn the circu- 

of h t e ixe°mood. lation or course of the blood in the 
body. This diagram* in the center of 

this plate will help us clearly to understand it. Here 
the heart (32) is laid open, showing its inner cham- 
bers and the valves between them. This large blood- 
vessel (16) is one of two great veins which empty 
the impure blood from the body into the right 
auricle of the heart. It is called the ascending vena 
cava, because it brings the blood from parts below 
the heart. Here (15) is the other of these large 
veins — the descending vena cava, bringing the 
impure blood from the upper parts. A valve pre- 
vents the blood from going back from the right ven- 
tricle into the auricle above. Here (21) is the 
pulmonary artery, which carries the blood from the 
right ventricle to the lungs. The blood is driven 
through this artery by the contraction of the muscle 
of the ventricle. Coming back from the lungs to the 
heart, the blood flows through this (23) pulmonary 
vein, which empties into the left auricle. From here 
it goes through a valve into the left ventricle. Now 
notice the thick muscle of the left ventricle. When 
this strong muscle contracts, the blood is forced out 
through this (24) great artery — the aorta, which 
branches out into many arteries and then into capil- 
laries all through the body. It will be well for 
you to learn and trace the course of the blood in this 
way: Coming impure from the body, it flows into 



* See plate showing "Formation and Circulation of the Blood." 



THE CIRCULATORY SYSTEM. 59 

the right auricle ; then through the valve into the 
right ventricle; then through the pulmonary artery 
to the lungs ; then through the pulmonary veins to 
the left auricle; then through the valve into the 
left ventricle; then through the aorta into many 
arteries ; then into the capillaries ; then into the veins, 
which return it to the heart. 

Three Divis- There are really three divisions of the 
ions of the circulatory system. The first is the 
course of the blood from the heart 
through the body for building and repair. The 
second is its course from the heart through the lungs 
for its purification. The third is a special course of 
a part of the blood through the liver. This is 
called the portal circulation. We see here (18) how 
several of these prominent veins gather the impure 
blood from these lower organs in the body, and, 
gathering into this (20) large vein, this blood is 
thrown into the liver, where it is partly purified, 
after which it is again collected by this upper (20) 
hepcdic vein, which turns it, as you see, into the large 
(16) ascending vein, which goes to the heart. 

w . The heart is, by far, the strongest 

Interesting ' » o 

Facts about the muscular part of the body. No 

Circulation. . . ,, -. -. « ., . , 

engine m the world, or its size, has 
so much strength. It beats about 100,000 times per 
day, 40,000,000 times per year, and in the life-time 
of an octogenarian 3,000,000,000 times without a 
stop! Its impulse is not only felt by its throbbing 



60 ELEMENTARY PHYSIOLOGY. 

on the walls of the chest; it may be easily felt at 
several other points quite remote from the heart 
itself, as, for instance, at the temples or at the wrists. 
These impulses, as felt at these places, are called 
the pulse. This index to the rate of the heart's 
action is very convenient to the physician, since it 
makes known to him at once any acceleration, retard- 
ation or irregularity of the blood's circulation. 

Health of t The steady and thorough work of the 
circulatory organs of the circulatory system is 
very essential to life and health. Any 
cause which tends seriously to increase or diminish 
the normal rate of the heart's action is a thing to be 
avoided. The ordinary quickening of the flow of 
the blood, as in moderate exercise of the body, is 
not only harmless, but healthful. Here, again, exer- 
cise must be commended as a prime condition of 
a healthy circulation. Any part of the body which, 
from any cause whatever, remains comparatively 
unused, will not be supplied by the circulatory sys- 
tem with a sufficient quantity of pure blood to main- 
tain its vigor. Such a part will therefore gradually 
wither and die. It follows that we need that kind 
of exercise regularly which will call into use all 
parts of the body, and thus prompt the flow of blood 
into every nook and corner of our physical structure. 

OUTLINE. 

THE CIRCULATORY SYSTEM. 
9 ( Central organ, the heart. 
( Arteries, blood-vessels leading from the heart. 



THE CIRCULATORY SYSTEM. 



61 



WHAT? 



" Veins, blood-vessels leading to the heart. 

Capillaries, uniting arteries and veins. 

Three divisions of the circulation: 

From heart to lungs and back to heart, for purifi- 
cation— pulmonary circulation. 

From heart to body and back to heart, for nutri- 
tion — systemic circulation. 

From veins of digestive organs through liver, for 
partial purification— por£a£ circulation. 



f Heart in chest, near middle. 
wheke? -{ Arteries, veins and capillaries distributed through- 
ly out the body. 



why? - 



To carry pure blood to all parts of the body. 

To gather up useless or waste material and carry 

it to the organs which remove it from the 

system. 



QUESTIONS. 

What can you say of the " wear and tear " of the body? 

What is the object of the circulatory system? 

What is the use of the blood? 

What are the organs and vessels of the circulation? 

Where is the heart situated? 

About how large is the human heart? 

Tell what you can about its purpose. 

How many chambers has the heart? 

Where is the right auricle? 

Where is the right ventricle? 

Where is the left auricle? 

Where is the left ventricle? 

What are the arteries? 

What kind of blood do the arteries usually carry? 

What are the veins? 

Do they usually carry pure or impure blood? 

Why do the veins have valves? 

What are the capillaries? 



62 ELEMENTARY PHYSIOLOGY. 

What changes in the blood take place in the capillaries? 
By what large vein is the blood from the lower body 

brought to the heart? 
By what large vein is the blood from the upper body 

brought to the heart? 
What prevents the blood from flowing backward from the 

ventricle to the auricle? 
What is the work of the pulmonary artery? 
What of the pulmonary veins? 
Why is the muscle of the left heart extra strong? 
What is the aorta? 
Now trace the course of the blood, beginning where it comes 

impure to the right auricle. 
How many divisions of the circulatory system? 
Why does the heart send the blood to the lungs? 
Why through all parts of the body? 

Why is a large part of the blood carried through the liver? 
What is meant by the pulse? 
What is the effect of exercise on the circulation? 
May exercise become too violent? 
How is the circulation affected in an unused part of the 

body? 
What is the best kind of exercise? 



THE RESPIRATORY SYSTEM. 



We have learned that the blood in its course 
through the body is made quite impure and needs 
to be repeatedly purified. For this purpose the 
body is furnished with the respiratory system. The 
chief organs of this system are the lungs, which lie 
in the chest, close around the heart. Let us get a 
clear and accurate idea how these important organs 
are situated. ( Turn to the body manikin. ) Here is 



THE RESPIRATORY SYSTEM. 63 

a manikin of the body. We will remove the outer 
muscles of the chest. Now, the ribs are before us. 
Eemoving these, the contents of the chest are shown 
precisely in their natural places. These (8, 9,) are 
the lungs. The heart liesQimmediately under and 
between them. 



The lungo are very spongy and light, 
fh rU ^un r s° f being composed largely of air-cells, 

whose walls are very delicate. These 
air-cells are all connected with tubes (Turn to (25) 
third section of lungs) and these tubes unite into 
this one large air-passage (24) called the trachea 
or wind-pipe. In the upper part of this wind-pipe, 
which comes close up to the mouth, the instrument 
of the voice, called the larynx, is situated. It is this 
(21, 22, 23), enlarged portion of the trachea. The 
exact structure of the larynx or voice-organ is shown 
by special sections above the lungs in the body mani- 
kin. This arrangement of these air-passages reminds 
one of an inverted tree. The larynx or voice-organ 
corresponds to the lower and thicker part of the trunk 
of the tree ; the trachea to the trunk itself ; the branch- 
ing air-tubes in the lungs to the branches and twigs, 
and the air-cells to the leaves. 



The pulmonary artery, which brings 
tise of the ^ e i m p Ure blood from the heart into 

Lungs. * 

the lungs, branches out (18) into many 
small capillary tubes which wind among and around 
these numerous air-cells. When the cells of th§ 



64 ELEMENTARY PHYSIOLOGY. 

lungs are filled with air, the oxygen of the air, in a 
wonderful way, passes through the wall of the cell 
and the wall of the capillary and unites with the 
blood. At the same time, impurities from the blood 
pass through capillary wall and cell wall into the 
cells and out through the air-passages with the 
escaping breath. In this way the blood is renewed, 
purified and brightened by the life-giving oxygen, 
and starts vigorously off on another round through the 
body. 

Breathing is the act of the body by 

which the lungs are filled with air and 
emptied again at proper intervals. This operation 
is so important and essential to life, that it has been 
entrusted to the performance of muscles of the invol- 
untary kind, that is, such as are not dependent on 
the direction of the mind. It is true, the will may 
interfere with the work of these muscles, so that we 
may suspend breathing to some extent. But it is 
Nature's plan that this work should be committed to 
faithful nerve-centers and muscles appointed for the 
purpose. It is well that this is so, for, otherwise* 
during sleep or other unconscious moments, when 
the mind gives no direction to the body, breathing 
would stop and life would end. Even when awake 
and in health, in this very busy age, we might for- 
get to breathe. 

The scientific name for breathing is 
Breathe respiration. That act of respiration 

which brings air into the lungs is called 



THE RESPIRATORY SYSTEM, 65 

inspiration; that which drives the air from the 
lungs, expiration. There are quite a number of 
muscles concerned in these acts. When the lungs 
are to be filled, these muscles expand the walls of 
the chest so as to enlarge the space inside. 
The air rushes in through the mouth, nose and wind- 
pipe, and fills the cells. Then a reverse action is 
produced by the muscles. The chest contracts and 
the air is forced out from the lungs by the same way 
through which it entered, but robbed of its oxygen 
and mixed with gases discharged from the body. 

Between the chest and abdomen is a 
ing Muscles, "broad partition muscle called the dia- 
phragm. This muscle is chiefly con- 
cerned in ordinary, gentle breathing. When the 
lungs are to be filled, the diaphragm moves down- 
ward, pressing upon the contents of the abdomen 
and enlarging the cavity of the chest, giving the 
lungs room for full expansion, provided the act of 
inspiration is unrestricted and complete. In expira- 
tion, the diaphragm rises and diminishes the capac- 
ity of the chest, forcing the air out of the lungs. In 
forced breathing, the muscles between the ribs, 
called the inter-cosial muscles (6, rib section), take a 
prominent part. These and other muscles also take 
more or less part in ordinary breathing. 

The inside of the chest is lined with a 

Plenrs. 

delicate web called the pleura. This is 
also spread as a covering over the lungs. It secretes a 



66 ELEMENTARY PR YSIOLOGY. 

watery fluid which keeps the walls of the chest and 
the surface of the lungs moist, and thus prevents 
friction which would otherwise be produced in the 
movement of breathing. The pleura is shown at (7 
on section of the ribs). An inflammation of this 
membrane is called pleurisy. When both pleura and 
lungs are inflamed it is called pleura-pneumonia. 

Health of the Fr ° m what We haYe leame d of the 

Respiratory structure of the chest and the action of 
the lungs in breathing, we can not fail 
to see that the healthy and natural action of the respi- 
ratory system requires perfect freedom of motion or 
expansion of every part concerned in the vital act of 
respiration. It is Nature's plan that every air cell 
in the lungs should perform its appointed part with 
all the rest, at every breath. If the habit of breath- 
ing, full and deep, while the chest is perfectly free 
to expand and the body is in erect or straight posi- 
tion, is well formed, every lung-cell will be filled at 
each inspiration. But if the chest is in any degree 
restricted and compressed, the lungs will be but 
partly filled, and many of the air-cells will lose their 
elasticity, and finally become utterly useless. Such 
an injurious interference with the natural expansion 
of the chest may be produced by habitual unnatural 
positions in sitting or walking, or by wearing the 
clothing too tight about the body. 

We have learned that the flow of blood 
through the vessels of the circulatory 



THE RESPIRATORY SYSTEM. 67 

organs is much quickened by exercise. So the rapid- 
ity of the flow of the blood through the lungs de- 
pends very much on the degree of our bodily activity. 
When we lie in bed, for instance, the circulation goes 
on very steadily, and our breathing is performed 
very moderately and quietly. But as soon as we 
arise and move about, both the circulation and respi- 
ration are quickened. The more vigorous the activ- 
ity of the body the more air is drawn into the lungs 
to purify the greater quantity of flowing blood. The 
chest muscles act more strongly and every cell in the 
lungs is inflated. All this tends to produce pure 
blood and active lungs, and, consequently, good 
health. 

The quality or purity of the air which 
ti^Breath ° f we breathe is quite as important as the 

quantity which we inhale. We have 
learned that the oxygen, which is one of the elements 
or gases which compose the air, is taken from the 
lung-cells to unite with the blood. This alone would 
make the breath which is given out impure because 
of its having been robbed of its oxygen. But the air 
which is forced out from the lungs is made much 
more impure by the gases which come from the im- 
pure blood of the body. These gases escape from 
the lungs at every breath. It is plain that if we 
breathe in a close room or in a confined body of air, 
every breath adds to the degree of impurity of the 
air, so that the latter becomes more and more unfit 
to breathe. It becomes unfit to sustain life, not only 



68 ELEMENTARY PHYSIOLOGY. 

because it is robbed of the life supporting oxygen 5 
but because one of the gases which are expelled from 
the body, by the breath, acts like a poison when it is 
inhaled (re-breathed) again. 

Ventilation means the furnishing of the 

Ventilation. ° 

needed supply of pure air. Nothing is 
more important in the line of hygienic or health pre- 
cepts than this, that we should avoid the breathing 
of air which has been made impure by the breath. 
To avoid this, it is necessary to have, at all times, 
a proper interchange between the air of a room and 
the pure, free air without. No person can remain 
long in a closed room without being injured by his 
own breath. There must be a place of escape for 
the impure air and a place of entrance for the pure 
air. Since impure air rises toward the top of a 
room, it escapes best from the opening of a wdndow 
at the top, while pure air enters best through an 
opening lower down. But without attempting to 
describe any of the numerous plans of ventilation, 
let this precept suffice: Get from the abundance of 
pure air which God has provided, as much as you 
can at every breath, and avoid, as a poison, the inha- 
lation of impure air. 

THE VOICE. 

The organs of the voice are so closely connected 
with the respiratory system that we will give a 
brief description of them here, 



THE RESPIRATORY SYSTEM. 69 

The chief organ of the voice is the larynx. 

This is really an expansion of the upper 
end of the wind-pipe, as already seen. 
The prominent point on the front of the neck, com- 
monly called "Adam's apple," is a part of the larynx. 
The cartilages of which the larynx is mainly composed 
form a sort of box, along whose two inner sides are 
stretched two membranous chords called the vocal 
chords. These come more or less closely together at 
the middle of the larynx, the slit or chink between 
them being called the glottis. Through this glottis 
every in-going and out-going breath ordinarily passes 
silently. But when the muscles which regulate the 
vocal chords tighten up these chords, while air is 
being expelled from the lungs, a sound is produced, 
either high or low, according to the degree of ten- 
sion, or tightness, to which the vocal chords are drawn. 
If you have learned to sing up and 
ment. XPCn down the eight tones of the musical 
scale, you may easily perform an experi- 
ment on the action of the muscles which control the 
tension of the vocal chords. Sound slowly the sylla- 
bles up and down the scale. You will feel a change 
in the contraction of the larynx muscles at every 
change of tone. Going up the scale, that is, to a 
higher and higher pitch, you will feel a tightening 
action of these muscles: coming down the scale to a 
lower and lower pitch, an opposite effect will be felt. 
The action of the breath on the vocal 
chords which has just been described, 



70 



ELEMENTARY PHYSIOLOGY. 



produces vocal sounds of different pitch. Their 
loudness depends upon the degree of force with which 
the breath is forced through the glottis. But this is 
not speech. To produce the articulate sounds of 
language, the sounds which are made by the vocal 
cords are very much modified and variously shaped 
by the changing position of tongue and mouth, which 
are produced in speaking. This is illustrated in 
every word we speak, and you will find it to be an 
interesting experiment to utter slowly the sounds 
which compose some word, while noticing the changes 
which you make in the position of your mouth and 
tongue. 

OUTLINE. 



THE RESPIRATORY SYSTEM. 



What? 



Lungs, very light and spongy, chiefly composed of 

air-cells. 
Trachea — commonly called wind-pipe. 
Larnyx — upper part of trachea, and organ of the 

voice. 
Air-passages through mouth and nose. 
Chief respiratory muscles — the diaphragm and 

inter-costal muscles. 



Where ? 



Lungs— in middle of the chest. 
Trachea — between throat and lungs. 
Diaphragm — between chest and abdomen. 
Inter-costal muscles— between the ribs. 



Why? 



f To furnish oxygen to the blood. 
1 To expel impurities which come from venous 
I blood. 



THE RESPIRATORY SYSTEM. 71 

QUESTIONS. 

What is the use of the respiratory system ? 
What are the chief organs of respiration ? 
Where are the lungs located ? 
Describe their structure ? 
What is the trachea ? 

What vessel brings the blood from the heart to the lungs ? 
Tell what takes place in the lungs. 

Is the act of breathing performed by voluntary or involun- 
tary muscles ? 
Why is this a wise provision ? 

What is meant by inspiration ? Describe the process. 
What is meant by expiration ? Describe the process. 
What is the lining membrane of the chest called ? 
What is the benefit of full and deep breathing ? 
What are the consequences of cramping the chest ? 
What is the effect of exercise on the lungs ? 
How is the air made impure by breathing ? 
Tell what you can of the necessity of ventilation. 
Where are the vocal cords ? 
How are the sounds of the voice produced ? 
How is the pitch of the voice varied ? 
How are the louder tones produced ? 
What other organs assist in forming the sounds of speech ? 



THE DIGESTIVE SYSTEM. 



Where does the building and repairing material, 
which is delivered to all parts of the body by the 
blood, come from ? How is it prepared and how 
does it find its way into the blood-vessels of the cir- 
culatory system ? These are some of the physiolog- 
ical queries which come to us now. 



72 ELEMENTARY PHYSIOLOGY. 



The matter of the body all comes from 

ng 
from Blood. 



Body-building Qur food< Tq provide our bodieg with 



such material, of good quality and of 
proper quantity, ought to be the main object of our 
eating. Not all of the food matter which we eat is 
useful in the body. So the means of separating the 
useful from the useless is necessary. Then, again, 
the useful parte of our food must be very much 
changed before they can be used by the building 
cells of the body. So the means for its proper prep- 
aration must be furnished. The system whose or-, 
gans prepare the needed elements of the food for 
the blood, and separate the useless from the useful 
portion, is called the digestive system. 

The preparation of food material for 
^fai^stem 8 " *^ e ^lood requires many operations. 

So the digestive system has a greater 
number of special organs than any other system of 
the body. We have seen how the movements and 
work of the circulatory organs depend upon the 
strength and prompt action of the muscles of the 
heart; also, how the respiratory system depends upon 
the muscular system in the steady and proper action 
of the breathing muscles. So, here, as we study the 
processes of the digestive system, we shall find how 
its work depends upon the muscles which are assigned 
to the duty of producing the necessary movements of 
its organs. Even the muscles of the arm and hand 
perform the very first act in the process of feeding 
the body, in properly bringing the food to the mouth- 



THE DIGESTIVE SYSTEM. 73 

The whole process of preparing food material for the 
blood is called digestion. The first step, that is, 
bringing the food into the mouth, is called prehen- 
sion. 

The second step in digestion is masti- 

t ° ti* ° f th€> ca ~ti° n ' This is performed in the mouth 
by the teeth. The mouth and the teeth, 
as used in chewing or masticating the food, have 
been called the mill of the body. The grinding in 
this mill is done by the muscles which move the 
jaws so as to produce a cutting, crushing or grind- 
ing effect upon the food by the teeth. 

There are thirty-two teeth in the full 
Xnmber of ge j. Q £ a pr rown person. These are set 

in sockets of the upper and lower jaw- 
bones — sixteen in each jaw. Eight front teeth — 
four in each jaw — are called incisors, or cutting 
teeth. On each side of these incisors — above and 
below — is a canine tooth. The two upper canines 
are often called eye-teeth, and the lower canines, 
stomach-teeth. These twelve teeth — eight are incis- 
ors and four canines — separate or bite off a proper 
portion from the food which is brought to the mouth. 
Next to the canines are two bicuspids, on both sides 
of each jaw. Bicuspid means having two roots. 
Then follow, as back teeth, three molars or grinders 
on both sides of each jaw. These twenty teeth — 
eight bicuspids and twelve molars — do the w T ork of 
crushing or grinding the food to a proper degree of 
fineness. 



74 ELEMENTARY PHYSIOLOGY. 

As we have already learned, a tooth 
st ^ uc !^ re of is not a bone. It does not belong to 

a Tooth. & 

the skeleton. The teeth are instru- 
ments or organs of the digestive system. The 
structure of a tooth is an interesting study. To help 
us understand it, we are provided, in the Anatomical 
Aid, with the means of completely dissecting — that 
is, separating into its parts, the structure of a tooth. 
In the manikin of a tooth, the little projecting 
ridges at the top (1) are called tubercles. The por- 
tion above the gum (2) is called the crown. This 
is covered by a thin layer of enamel, the hardest 
material in the body. The tooth is mainly composed 
of a substance called dentine, or ivory (9). At (6) 
and (7) the roots of the tooth are shown. At (12) 
blood-vessels and nerves are seen to enter into 
the tooth. When an opening occurs in the body of 
the tooth, from decay, this nerve is exposed to the 
air and the action of food particles, and toothache 
is the result. 

The third step in digestion is insaliva- 
salivary tion. Really, mastication and insaliva- 

tion are performed at the same time. 
While the food is being chewed by the teeth, a liquid 
is mixed with it in the mouth. This liquid is spe- 
cially prepared for this purpose, from the blood, by a 
number of organs called salivary glands. By the 
way, let us not forget that all the substances of the 
body are prepared from the blood. A gland is an 
organ which secretes — which means separates — some 



THE DIGESTIVE SYSTEM. 75 

special or peculiar substance from the blood. So, 
one of the glands of the eye secretes tears, and the 
salivary glands secrete saliva. Three pairs of these 
glands are quite prominent. The largest pair is 
just below and in front of the ears. The second pair, 
in size, lies under the jaw-bone, and the third pair is 
under the tongue. These glands, between meals, 
furnish enough saliva to keep the mouth moist. But 
when food is taken into the mouth and chewed, or 
even at sight of something tempting to the taste, 
they furnish it in great abundance. It not only 
moistens the food so that it may be easily swallowed, 
but it also begins the process of changing the food 
material. 
„ T , ^ , The fourth step in digestion is swal- 

Work of the . . . 

Pharynx and lowing. This is a much more familiar 
oesophagus. wor( j ^ lan deglutition, which is the sci- 
entific name for the same act. When the food has 
been properly prepared in the " mill of the mouth," 
it is swallowed, or sent to the stomach. The cavity 
back of the mouth is called the pharynx. Between 
the pharynx and the stomach (refer to body manikin) 
is this tube (35) called the oesophagus. By the 
action of the muscles of the pharynx and the oesopha- 
gus, the food is moved into the stomach. This is 
deglutition. 

We have now traced the course of the 
work of the fofift i n to the main organ of digestion — 

Stomach. ° o 

the stomach. Here its greatest change 
is to be produced. The position of the stomach 



76 ELEMEN TARY PHYSIOLOGY. 

should be well understood. Observe it carefully in 
this manikin (31). The stomach has three coats or 
walls. The outer coat is thin and smooth, and fitted 
for the protection of this organ in its contact with 
other organs. The inner coat — called the mucous 
wall — contains many little glands or cells, which 
secrete a substance which is very important in the 
process of digestion. It is called the gastric juice. 

When food comes into the stomach the 

T^ 8 ® * 1 ^. gastric iuice is mixed with it. This 
Gastric Juice. Y . . . 

intermixing is made quite thorough by 
the action of the muscles which compose the middle 
coat of the stomach. As long as there is food 
within it, these muscles keep up a churning motion 
of the organ. The result of the action of the gastric 
juice is that the food is very much changed in its 
nature and appearance. It is now called chyme, and 
the change which has been produced in the stomach, 
chymification. 

At the right end or discharging open- 

p V °ioru°s ftlie * n S °^ ^ e s ^ omac l 1 i s placed a muscular 
valve called the pylorus. This name 
means gate-keeper. The pylorus is a door-keeper of 
the stomach. Such portions of the contents of the 
stomach which have been properly changed into 
chyme, it allows to pass out, but refuses passage to 
other portions. Much depends upon the faithfulness 
of this pyloric muscle. When from any cause it 
loses its power, or refuses to act, the food escapes 



THE DIGESTIVE SYSTEM. 77 

from the stomach before it is prepared to enter the 
intestines, which is a form of indigestion which soon 
destroys life. 

The Liver, as the manikin shows, is a 
th°iy ° f • very large organ overlying the stomach. 

It weighs from three to four pounds. 
It is both a blood-purifying and a secretory organ. 
As a secreting organ, it performs its part in the 
process of digestion by furnishing a substance called 
bile, which it sends through a duct or tube into the 
duodenum, or upper part of the small intestines, 
where it aids in further change of the chyme 
which has just passed into the intestines from 
the stomach. 



Back of the stomach lies the pancreas 

ie 
Pancreas. 



IVorkofthe (59^ TMs organ f urnishes a fl u id 



called the pancreatic juice, which is also 
brought into the duodenum. The action of the bile, 
the pancreatic fluid and the intestinal juice, is to 
change the chyme into chyle, and to separate the 
useless or waste portion of the food. This waste 
portion is carried out of the body by way of the 
intestines, and the useful portion, having undergone 
all the processes of digestion, is now ready to be 
given to the circulatory system for transportation 
to every point of demand. How tlie chyle is trans- 
ferred from the digestive organs into the blood will 
be shown in the next chapter. 



78 ELEMENTARY PHYSIOLOGY. 

Perhaps no system of the body is more 
Health of the r J J 

Digestive carelessly or more frequently abused 

system. than the digestive system. No system 

of the body brings back upon the abusing offender 

a severer penalty of discomfort. Proper digestion is 

the very first condition of good health. Hence the 

hygienic principles referring to this system should 

be carefully learned and regarded. 

The injury resulting from eating too 
Eating Too £ as ^. comes chiefly from this, that the 

processes of mastication and insaliva- 
tion cannot be properly performed. Unless the 
food is properly chewed, and thoroughly mixed with 
saliva, its digestion in the stomach will be either 
much retarded or left incomplete. 

The capacity of the stomach is limited. 
Eating Too j£ « t j overloaded, it can not thoroughly 

Much. ' *=> J 

digest its contents. Besides, the gas- 
tric juice is also limited in quantity, and will not 
completely change into chyme more than a proper 
portion. 

Between the digestive operations of the 
Eating too stomach it needs intervals of rest. If 

Frequently. 

food is taken too frequently, it loses its 
vigor, and soon fails to perform its work in a healthy 
manner. 

Some articles of food, though very 
3e Food, tempting to the taste, are very "trying " 

to the stomach. It is plain, that, if 



THE DIGESTIVE SYSTEM. 



79 



Exercise. 



these are too frequently eaten, the stomach's action 
will be greatly impaired. If eaten at all, they 
should be sparingly mixed with more digestible 
food. 

Gentle exercise is very helpful to diges- 
tion. But violent exercise, either just 
before or after a meal, is quite as injurious. A 
cheerful state of mind is very helpful in keeping up 
a healthy action of all the digestive organs. 

OUTLINE. 

THE DIGESTIVE ORGANS, 
f Teeth— 32 in full set. 
Salivary Glands— three pairs. 
Muscles of Pharynx and (Esophagus. 
what? i Stomach. 
Liver. 
Pancreas. 
Intestines. 
r Teeth— in sockets of jaw-bones. 
Salivary Glands — located about the mouth. 
Pharynx and oesophagus — funnel and tube — 

between mouth and stomach. 
Stomach — under diaphragm in abdomen. 
Liver — overlying the stomach. 
Pancreas — lying back of the stomach. 
Intestines — filling lower abdomen. 
Teeth— to masticate the food. 
Salivary Glands — to furnish saliva. 
Muscles of pharynx and oesophagus move the food 

from mouth to stomach. 
\ Stomach — to change food to chyme. 
Liver — to furnish bile. 
Pancreas — to furnish pancreatic juice. 
Intestines— to complete the work of digestion and 

separate the chyle from the waste matter. 



whebe? i 



WHY , 



80 ELEMENTARY PHYSIOLOGY. 

QUESTIONS, 

From what does all the body material come? 

What processes are necessary to fit food for body nourish- 
ment? 

What is the name of the system which performs these pro- 
cesses? 

What is the first act in the process? 

What steps take place in the mouth? 

How many teeth in a full set? 

Name the different kinds of teeth. 

How is the food conveyed from the mouth to the stomach? 

Describe the work of the stomach. 

By what means is the gastric juice well mixed with the food? 

What is the food, as it leaves the stomach, called? 

Describe the action of the pylorus. 

What does the liver furnish for the work of digestion? 

What is furnished by the pancreas? 

What is the chyle? 

What are the consequences of eating too fast? 

What results from over-eating? 

What from eating too often? 

What from eating indigestible food? 

What are the effects of exercise on the digestion? 



THE ABSOBPTIVE SYSTEM. 



In previous lessons we have learned how food is 
prepared by the organs of the digestive system and 
reduced to a fluid state. Let us also recall what we 
have learned of the circulatory system; how the 
blood is constantly making the circuit of the body, 
carrying food to every tissue. 

The sixth plate of the Anatomical Aid shows most 
admirably all the organs and parts concerned in the 



THE ABSORPTIVE SYSTEM. 81 

two processes just referred to, and a careful stu^y 
of this plate will enable us to understand their rela- 
tion to and connection with each other. How, then, 
does the digested food get into the circulation? 
What provision is made for transferring it from the 
alimentary canal to these blood-vessels ? To answer 
these questions, we must first study how food is 
absorbed. 

The food in its liquid form must in the 

Absorption. x 

first place be removed from the stom- 
ach and the intestinal tube. This is accomplished 
by a process called absorption. This work may be 
more easily comprehended by first referring to a 
similar process constantly going on in vegetable 
growths. Planted in good soil and supplied with 
water, a plant will send out its small rootlets, whose 
little mouths will drink in [absorb) mineral sub- 
stances from the soil dissolved by the water. This 
liquid plant-food is carried by the sap [vegetable- 
blood) up the trunk or stem to nourish the parts of 
the plant. There is a similar provision for taking 
up the liquid food from the alimentary canal. There 
are little rootlets provided for this w T ork whose action 
resembles that of the root-fibers of the plant. 

The inner wall or coating of the small 
5?Jj. stinal intestines has a velvety or plush-like 

appearance. This is due to the myri- 
ads of little hair-like projections, which hang down 
from the inner walls and point toward the center of 
the tube. These small cones or fingers are called villi. 



82 ELEMENTARY PHYSIOLOGY. 

They are very numerous, covering the intestinal 
membrane as with a coat of hair. The word signi- 
fies hair-like bodies. These villi, which dip into the 
liquid contents of the alimentary canal, are not 
themselves the absorbents; but they contain small 
rootlets which take up the food and start it on the 
way toward the heart. 

In each villus {singular of villi) there 
Two Classes are two kinds of little workers gather- 

of Absorbents . . 

in tiie Villi, i^g up different kinds or rood particles 
from the liquid mass in the intestines. 
These are known as blood-vessels and lacteals, and 
are the starting points of two different routes by 
which the food is carried to the heart and into the 
circulation. 

The blood-vessels or veins are arranged 
veins in tne arourK j the center of the villus, form- 

Villi. 

ing a sort of net- work. They all unite 
and form one large vein, plainly shown here on the 
Aid (20). This vein is called the portal vein. 

Portal The route by which the blood and food 

circulation. carr i e d by the veins reach the heart 
constitutes the portal circulation, which we will 
now consider a little more fully. The portal vein 
(20) empties its contents into the liver (33) from 
below, and divides and subdivides, finally forming 
the capillaries of the liver. The structure of the 
liver is shown by the Aid at (18) {under microscopic 
structure of the textures). In the liver an important 



THE ABSORPTIVE SYSTEM. 83 

process takes place. The bile is secreted from the 
venous blood, and stored up in the gall-bladder, to 
be used when needed in the digestion of food. The 
blood, after being robbed of its bile and changed in 
other respects not well understood, is again collected 
and carried upward by the hepatic vein (20) and 
emptied into the lower vena cava (16), which in turn 
pours it into the heart, as shown here by the Aid. 
This completes the portal circulation. 



Now let us go back to the same start- 

The Second j n g point, and trace other portions of 

the digested food by another route; 

but which will ultimately lead to the same cavity of 

the heart. 

At this point we should observe how nicely every 
organ of the body is adapted to perform its own 
specific work. The blood-vessels spoken of under a 
preceding head take up from the stomach and intes- 
tines only certain portions of their contents, to do 
which, they seem especially adapted. Other portions 
are absorbed by the lacteals, which seem to be par- 
ticularly suited for this purpose. 

Extending lengthwise through the cen- 
iLacteais in ter f h uttl vin surr0 unded by 

the \illi. ' ." ' . 

the meshes of the small veins just 
described, is a single minute duct or rootlet called a 
lacteal. Lac means milk, and it is owing to the 
milk-like appearance of their contents that the term 
lacteal is applied to these vessels. 



84 ELEMENTARY PHYSIOLOGY. 

As in the case of the blood-vessels, 
chyiiferous w hich are the beginnings of the portal 

Vessels and & to * 

JLympiiatie circulation, so the lacteals unite and 
finally form the thoracic duct (10). 
Just as small creeks flow together and form larger 
streams, so the lacteals form chyliferous vessels, 
which are shown here at (7) on the Anatomical Aid. 
These vessels carry the chyle absorbed by the lac- 
teals through numerous glands called lymphatic 
glands (6), and finally empty it into the chyle recep- 
tacle, which is seen here at (9). 

The chyle receptacle is a sac-like expan- 
Thoracic g - ou Q £ ^e lower end of the thoracic 

l>uet. 

duct, which is about as large as a slate 
pencil or goose quill. The direction in which it 
carries the chyle is very plainly seen by referring to 
the Aid. It passes upward in front of the spinal 
column and behind the oesophagus (2). At its upper 
end it bends forward and downward, something like 
the crook of a walking cane, and pours its contents 
into the left subclavian vein. From this point the 
chyle passes into the innominate vein (14), and then 
through the upper vena cava (15) into the right 
auricle of the heart. 



Thus we have traced the different sub- 
seen Done. 



stances of which the digestive food 



is composed by different routes to the 
same cavity of the heart, there to mingle with each 
other, and with the impure blood collected from all 



THE ABSORPTIVE SYSTEM. 85 

parts of the system. We have found the viaduct 
which spans the gap between the digestive and cir- 
culatory systems. 

The food is now in charge of the great 

Assimilation. . ., . 

carrier, the blood, which is propelled 
by the heart to the lungs to be purified ; is returned 
to the right side of the heart, whence it is driven 
out through the great aorta, through the divisions 
and subdivisions of which, the blood reaches all 
parts of the system. Now, just as a freight agent 
at a railway station takes from a stopping train just 
such freight as is intended for his particular station, 
so every tissue of the body selects just such parts 
from the blood as it can appropriate to its use or 
u+ilize in repairing itself. The bones take from the 
blood such material as will make bone-cells; the 
muscles will select such as will make muscular tis- 
sue. In this way every part of the body is nour- 
ished, and the wonderfully mysterious process by 
which each cell and tissue selects materials brought 
to it for its growth and development, is called assimi- 
lation. This term is appropriate, because it means 
making like. 

RECAPITULATION. 

So that the important processes which we have just 
been considering may be impressed upon our minds 
and remembered, let us recapitulate by tracing a morsel 
of bread and butter from the mouth to the tissues of the 
body nourished by it. "Bread and butter" may be 
considered as an almost perfect diet since it con- 



56 ELEMENTARY PHYSIOLOGY. 

tains nearly every ingredient necessary to sustain 
life. The bread represents one class of food, and 
the butter another class. 

1. It is masticated in the mouth, and 
thoroughly mixed with the saliva. 

2. By the action of the muscles of the pharynx 
and oesophagus (2), it is forced into the stomach (1). 

3. In the stomach it is acted upon by the gastric 
juice and most of it digested. 

4. It is forced through the pylorus into the small 
intestines. 

5. Here it is absorbed principally by the blood- 
vessels of the villi. 

6. The small veins now carry it into the portal 
vein (20), which empties it into the liver (33) from 
below. 

7. It passes out of the liver and is carried by the 
large vein (16) into the heart. 

8. It is carried with the blood to the lungs, and 
returned as red blood. 

9. It is pumped by the heart to all parts of the 
system. 

10. It is assimilated by the various tissues. 

1. It is masticated with the bread. 

The Butter. . __ 

2. It is swallowed. 

3. It passes from the stomach to the intestines 
unchanged. 

4. By the action of the bile and pancreatic juice, 
it is converted into chyle. 



THE ABSORPTIVE SYSTEM. 87 

5. Being fatty substance, it is absorbed chiefly by 
the lacteals. 

0. The chyliferous vessels (7) carry it through 
the lymphatic glands (6) into the chyle receptacle (9). 

7. The thoracic duct (10) empties it into the 
subclavian vein at 11, by which it reaches the right 
auricle of the heart. 

8. From this point the two kinds of food travel 
together toward the outposts of the body, carrying 
nourishment wherever needed. 

THE LYMPHATIC VESSELS. 

Besides the blood which is found cir- 
culating in all parts of the body, there 
is another fluid, almost colorless in appearance, 
which is also found widely distributed throughout 
the system. This fluid is called lymph, which sig- 
nifies transparent fluid. In composition the lymph 
closely resembles the plasma of the blood, and con- 
tains minute bodies or corpuscles resembling the 
white corpuscles of the blood; these are called 
lymph globules or lymph corpuscles. 



This fluid is supposed to be mostly 
f 

Lymph. 



worn-put materials gathered from all 



parts of the body. It consists probably 
of portions of blood-ingredients which have oozed 
through the walls of the arteries, veins and blood- 
capillaries, together with certain products of the 
combustion which takes place in the body. These sub- 
stances are gathered up by tiny vessels, and, after 



88 ELEMENTARY PHYSIOLOGY. 

being worked over in a manner not well understood, 
they are capable of further use in the body. Thus 
we see a wise economy in allowing nothing to go to 
waste which can in any way be put to further use. 
This reminds us of the economy practiced in sifting 
coal ashes taken from our stoves and furnaces, sav- 
ing therefrom such partly burned coal as may be 
capable of giving off more heat if put into the fire 
again. 

The vessels which carry the lymph just 
i^m hatics described are called lymphatics. They 

are more delicate in their structure than 
the veins and arteries and permeate every part of the 
body. Wherever blood capillaries are found, there 
lymph capillaries are also found, though on account 
of their minute size they can not be seen until injected 
with mercury or some colored fluid. They vary in 
number with the variation of the number of blood 

vessels. 

The functions of the lymphatics of the 
T J ie f iym " system may be regarded as similar 

phatics, a J J & 

System of to those of tiles, or drain pipes, which 

Drainage. „ „ ,, , . , 

rarmers so frequently lay m wet, 
swampy lands for the purpose of carrying off the 
surplus water. The water soaks into these tiles, 
which carry it off under ground, thus drying the field. 
Likewise the surplus fluids which collect in all parts 
of the body are absorbed by the lymphatics — the 
drain pipes of the body — which unite, forming 
larger vessels, which empty into the thoracic duct, with 
the contents of which the lymph reaches the heart. 



THE ABSORPTIVE SYSTEM. 89 



In all parts of the system the lymphat- 

phatic Glands. 



ics pass through small bodies called 



lymphatic glands, which vary in size 
from that of a pin-head to an inch in diameter. It 
is not definitely known what the function of these 
glands is; but it is probable that they renovate or 
work over the waste and surplus material brought 
to them by the lymphatics, and that the lymph 
globules originate in them. Whether this is true 
or not, there can be no doubt that these glands are 
essential to health; because, when they become 
hardened or inflamed, as is often the case in persons 
of a scrofulous tendency, health fails and the patient 
grows thin and emaciated, even though his diet may 
be of the proper kind and quantity. 

The lacteals, which we have considered 

The ^Lacteals, 

a Part of the in connection with the absorption of the 
ymn a ics. £ OQ( j f rom the alimentary canal, are a 
part of the lymphatic system. They constitute that 
portion which begins in the villi of the intestines. 
When the process of digestion is completed, they 
serve as drain-pipes, like the lymphatics in the system 
at large. Their special work, however, is that in 
connection with the absorption of fatty food through 
the walls of the intestines. 

We have learned how the blood "dr- 
ies compared culates;" how it starts from the heart 

with the an( j a fter making the complete circuit, 

Blood-vessels. & . 

is brought back to the heart again. We 



90 ELEMENTARY PHYSIOLOGY, 

have learned also that the blood-vessels both give 
off tissue-making substances and take on waste and 
worn-out material, which they carry away. In con- 
trast with this the lymph does not "circulate." It is 
carried toward the heart, where it enters the life- 
giving stream — the blood. In the lymphatic system 
there are, therefore, no vessels to correspond with 
arteries. Again, the lymphatics collect worn-out tis- 
sues, etc., but give nothing in return. 

„ The work of the lymphatics is not con- 

Otlier Func- J # L 

tions of the fined to the absorption of food from the 
lymphatics. i n t es ti nes an( j collecting surplus and 
waste materials from the system in general. Certain 
other phenomena, all of which are of interest to us, 
are due to the absorbing power of these vessels. For 
instance, when a poisonous substance is placed upon 
the skin the lymphatics at once absorb it and carry 
it into the circulation. The lymphatics of the lungs 
take in the poison of disease and diffuse it through- 
out the system. When the appetite fails during 
long-continued illness, life is sustained by the uncon- 
scious consumption of one's own flesh, which is 
absorbed by the lymphatics and carried out into the 
circulation. 

In a similar manner, as we will learn further on, 
the poisonous nicotine of tobacco is absorbed in the 
lungs and the system poisoned. Thus we see that 
these vessels, which are ever active, take up, indis- 
criminately, foods, poisons, medicines, or the waste 
of worn-out material. 



THE ABSORPTIVE SYSTEM. 



91 



In concluding our consideration of the 

Suggestions ° 

to the absorptive system, let it be suggested 

that the Anatomical Aid be constantly 
referred to. In all topics discussed, it will be an 
Aid indeed, and the work be made incomparably 
more effective. 

OUTLINE. 

Food is absorbed. 
It is conveyed to the circulation. 
Surplus and worn-out tissues are collected. 
They are renovated and prepared for use, and are 
again thrown into the blood to be used. 



What? 



Where? 



In the walls of the alimentary canal. 
In the system at large. 
In the tissue of the skin. 
In the cells of the lungs. 
Wherever blood-vessels are found. 



Why? 



I 



To collect and transfer material. 



QUESTIONS. 
What is absorption? 
How do plants illustrate the manner in which food is taken 

from the intestines? 
What is there in plants to correspond with blood in animals ? 
What gives the lining membrane of the intestines its smooth, 

velvet-like appearance ? 
What do the intestinal villi contain ? 
Describe their structure. 
What is the portal vein ? 
Trace the food absorbed by the veins, from the intestines to 

the heart. 
How is the blood changed in its passage through the liver ? 
Where is the hepatic vein ? and what is its function ? 
What are the lacteals ? What is their function ? 
Of what general system are they a part ? 



9 2 ELEMENTARY PHYSIOLOGY. 

Through what glands do they pass ? Into what do they 

empty ? 
What is chyle ? Why are the lacteals so called ? 
What are the chyliferous vessels ? 
Describe the thoracic duct. Locate it. 
What is the chyle receptacle ? Describe it. 
Explain assimilation. Where does it take place ? 
Trace a mouthful of food from the mouth to the tissue in the 

body. 
What is lymph ? What does it resemble ? 
What are lymph globules ? 
Explain the origin of lymph. 
What vessels carry it ? Describe fully the action of the 

lymphatics. 
With what may they be compared ? 

In what respects do the lymphatics differ from the blood- 
vessel of the general circulation ? 
What is the difference between lymph and blood ? 
Explain how the lymph vessels constitute a drainage system 

of the body. 
Whither is the lymph carried ? 
What are lymphatic glands ? Describe them. 
What effect have they upon the general health when they 

become diseased or hardened ? 
Why should we be careful not to touch poison ivy ? 
What danger is there in breathing the air of a sick chamber? 
When a squirrel or other animal hibernates, on what does 

it subsist ? 
Why is medicine sometimes injected under the skin, and 

how is it rendered effective ? 
Name all the vessels which constitute parts of the absorptive 

system. 



THE EXCRETORY SYSTEM. 93 

THE EXCRETORY SYSTEM. 



It will be remembered that the material collected 
by the lymphatics is priDcipally such as is capable 
of being worked over in the little workshops, the 
lymphatic glands, and used again as building mate- 
rial of the body. 

There is, however, much waste matter which can 
not be thus elaborated for further use in tissue- 
building; and yet some of this material is taken 
from the blood by organs adapted to this particular 
purpose, and converted into substances essential to 
some of the vital processes. Other parts are fit for 
nothing whatever, and must be expelled from the 
system, because, if allowed to remain in the blood, 
they would not only be useless, but an actual poison 
to the system. 

The organs whose function it is to take 

The Excre- ° 

tory from the blood such substances as can 

not be utilized again in the body -build- 
ing process, but which must either be changed into 
some other substance, or expelled from the body, 
are the lungs, liver, kidneys and skin. Each of 
these is suited to take from the blood its own kind 
of impurities, and either elaborate them into some 
usable substance or start them in their course lead- 
ing from the body . 



94 ELEMENTARY PB YSIOLGGY. 

THE LUNGS. 

The excretory functions of the lungs 

Impurities . 

Tin-own off [Turn to manikin of the body, 8, 9.) 
bytiie^unss. haye been referred to under jRespz'ra- 

tion, and their structure there explained. The pure 
air, taken into the lungs, gives up its life-giving 
oxygen, and in return becomes heavily loaded with 
carbon dioxide, or, as it is more commonly called, 
carbonic acid gas. 

The chief of the excretions f»rom the 
moxide lungs is carbon dioxide. It is a re- 

sult of the union of the oxygen of the 
air inhaled, and carbon from the tissues of the body* 
This compound will not only fail to support life, 
but is an actual poison. 

The destructive nature of this gas is 

Carbonic Acid .ii , . ■• . A £ 

Test> illustrated in many ways. As tor in- 

stance, if a man goes down into a well 
and is overcome, becomes unconscious and helpless, 
it is this gas which causes his condition. It is of 
the same kind as that which is thrown off by the 
lungs, is colorless, and is heavier than air, and conse- 
quently settles to the floor, or into cellars, wells, etc. 
Therefore it is safer to sleep on a bed than on the 
floor, since this deadly gas settles, during the night, 
on the floor. 

As it w r ill not support life in man and animals, so 
it will not support combustion, or burning. Hence, 
if it should become necessary to go down into a well. 



THE EXCRETORY SYSTEM. 95 

it would be advisable to first lower into it a lighted 
candle. If the candle continues to burn, it may 
be concluded that the well is sufficiently free from 
carbon dioxide to enter it with safety. 

That the lungs expel a gas which is 
Test of the identical with that which collects in 

Breath. 

wells may be illustrated by breathing 
into a glass jar, after having held the breath in the 
lungs for some time. If a lighted taper or wax 
candle be lowered into the jar containing this 
exhaled breath, it will go out, thus showing the 
absence of pure air and the presence of carbonic 
oxide. Again, to show that other substances, such 
as particles of animal matter, are contained in air 
once breathed, let the contents of the lungs after a 
full inspiration be breathed into a bottle and corked 
up. The effete matter excreted with the breath will 
decompose and soon give off an offensive odor. Thus 
we may understand the need of ventilation already 
mentioned. We can understand how the excretions 
from the lungs soon make the air in a closed room 
unfit for breathing, causing drowsiness and headache. 
The especial need of well- aired school-rooms is 
therefore urged for the consideration of teachers 
and pupils. Let pupils make the simple tests men- 
tioned and see for themselves the importance of 
proper ventilation. 

Besides what has already been men- 

E X hare y d VaPOr tioned > tlie luG g s take from the blo °d 
a watery vapor which is ordinarily not 



96 ELEMENTARY PHYSIOLOGY. 

visible, but in cold weather is condensed and collects 
on the windows, or can even be seen as it comes with 
the breath from the nostrils or mouth. It is chiefly 
the vapor of alcohol which is expelled from the 
lungs of a person who has used strong drinks, and 
his breath thus tells the tale of his indulgence. It 
has been carefully estimated that about one or one 
and one-fourth pounds of water is daily given off 
with the breath of a man. 

THE LIVES. 

The liver, and its connection with the 
for^o^aT process of digestion and also the portal 

circulation have been spoken of else- 
where. But it must also be considered as an excre- 
tory organ. Its function is not merely to secrete 
from the blood a fluid needed in the process of 
digestion, but by so doing it acts as a blood pitrijier. 
It is a well established fact, that, in case of a diseased 
liver, when that organ fails properly to perform its 
work of secreting the bile, which thus remains in the 
blood, a disease known as jaundice ensues, and, if 
this disease is not checked, the person dies with 
symptoms of poisoning. 

THE KIDNEYS. 

The kidneys are two bean-shaped bodies, a little 
more than half as large as the closed fist. They 
are located in the back part of the abdominal cavity, 
one on each side of the spinal column. Their shape, 
size, appearance, color and structure are very 



THE EXCRETORY SYSTEM. 97 

plainly shown by the Anatomical Aid [manikin of 
the body). These dark-colored little glands have a 
very important function to perform. They cannot 
delegate their work to any other organ of the body, 
as is the case with some of the other glands. They 
alone can perform the work assigned them. Hence, 
when diseased, their work is not done, and sickness 
ensues. 

The particular and only work of the 
Kidneys. kidneys is to separate from the blood 

brought to them, a substance called 
urea. This is a very poisonous matter, which, if 
not removed from the body by the healthy action of 
the kidneys, will accumulate, and finally cause 
death. 

The renal arteries (g) constantly carry 
at Work. * to the kidneys a portion of the blood, 

which passes through the capillaries of 
the kidneys, as seen by turning back the first sec- 
tion of the right kidney of the manikin. The 
blood is again collected by the veins, and conveyed 
through the renal vein (h) to the large veins lead- 
ing to the heart. In the capillaries of the kidneys 
the blood loses its watery part, which carries, in so- 
lution, impurities called urea. This watery fluid 
soaks through the thin capillary walls, is collected 
and conveyed by two tubes (56), called ureters, to 
the bladder (57), whence it is expelled from the 
body. 



98 ELEMENTARY PHYSIOLOGY. 

Difference be- ^- s ^ as been shown, the bile, secreted 
tween Seere- from the blood, is utilized in the diges- 
i.iveraii<i tive process. But the secretions 
Kidneys. Q £ ^xq kidneys are poisonous to the 

system, cannot be used in any process whatever, 
hence must be at once removed from the system. 
Thus the kidneys are exclusively excretory organs. 



LESSONS FROM THE MICROSCOPE. 



There are about us myriads of wonder- 
ful creations which cannot be perceived 
by our unaided senses. Our sense of sight is not 
sufficiently acute to see the countless numbers of 
minute living bodies which throng every drop of 
water taken from a pond. TV 7 e can not see the tiny 
corpuscles which float in the blood and give it its 
color, just as indigo dissolved in water will give it a 
blue color. Many persons know nothing of the 
w r ondrous beauty with which God has clothed the 
insects which swarm about us. With the unaided 
eye w r e see no beauty in the so-called dust which 
covers the w T ings of our moths and butterflies. But, 
when we call to our aid proper instruments, made 
for the purpose, the dust on the wings and body of 
the butterfly is at once transformed into beautifully 
formed scales, of brilliant rainbow colors and the 
most perfect shape and structure. The instrument 



LESSONS FROM THE MICROSCOPE. 99 

constructed to aid us in seeing things which are too 
small for us to see without this apparatus is the 
microscope. Its structure and principles upon which 
it operates, can not here be explained. Let it be 
sufficient to say that the microscope is a combina- 
tion of glass lenses so arranged as to make things 
seen through it much larger. If you take your 
grandmother's spectacles and hold them just right, 
objects seen through the glasses will appear larger. 
In a similar way and for a similar purpose the glasses, 
or lenses, of a microscope are used, only that the 
microscope makes a much greater difference in the 
apparent and real size of objects seen through it. 

MICROSCOPIC STRUCTURE OF THE TISSUES. 

As the minute scales of the butterfly 
scope as an can n °t be satisfactorily examined with- 
Aid in ou t- £h e microscope, so the proper and 

Physiology. L ' x i 

successful study of the different tissues 
of the body requires the aid of this instrument. And 
since it is not possible for all pupils to have access 
to a microscope, it is fortunate that those wdio have 
made physiology a careful study, and have examined 
the various structures and tissues with great care, 
have made drawings and sketches which we may 
study. Thus we have here on the Aid a series of 
marvelous paintings, true to nature, which we can 
study with even more satisfaction than if we were to 
prepare the specimens and look at them through the 
microscope ourselves. We have spoken of the body 



100 ELEMENTARY PHYSIOLOGY. 

as " the house in which we live." We may carry the 
comparison a little farther and consider the different 
tissues as the material used in the body-building, 
where they serve a purpose much like that of sand, 
stone, lime, glass, bricks and so on, in the construc- 
tion of a building. 

MICROSCOPIC STRUCTURE. 

Here (1) we see the three coats of the 
teries (l)" arteries. The outer layer is made 

up of a fibrous matter, more or less 
elastic. Next to it lies the middle coat, which 
consists of alternating layers of elastic tissue and 
muscular fibers, and the inner lining consists prin- 
cipally of a net-work of elastic tissue. 

As in the arteries, the veins under the 
Vein^ (2) microscope show three distinct coats, 

but the entire vein wall is much thin- 
ner than that of the artery. Here at (2) the structure 
of the vein is shown. We see also the valves, men- 
tioned under the circulation, which consists of pouch- 
like folds of the inner coat. Here we see three 
valves; but sometimes there are but two, and even 
one. From their shape and position you may see 
that they will allow blood to pass through them in 
one direction, but not in the other. Thus, blood can 
not flow backward, which, you will perceive, is a very 
wise provision. The shape of these valves as shown 
here will suggest the appropriateness of the name, 
semilunar valves. 



LESSONS FROM THE MICROSCOPE. 101 

of capiiia- At (3) we have represented the net- 
ries between W ork of capillaries which constitutes 

Arteries , x 

and veins (3). the connection between the arteries and 
veins. Here the outer and middle walls of the 
arteries have disappeared, and only the inner coat 
remains. The filtering process can thus take place 
with little difficulty. 

of iiucous All cavities of the body which corn- 
Membrane (4.) municate directly or indirectly with 
the outside surface are lined with a soft, smooth 
membrane called the mucous membrane. This is a 
continuation of the skin. At the lips, for example, 
we may see that the skin merges into a softer and 
more sensitive coat, the mucous membrane. Here, 
at (4) you may notice its net-work of capillaries. 
Li o edca n ^t (5) we see the capillary meshes of 
lariesoftne the skin. Through their folds are 

absorbed many substances which are 
then carried into the system, as we learned under 
Absorption. The activity of these capillaries as 
absorbents makes it possible for sailors to quench 
thirst by spraying their garments with sea water 
when their supply of fresh water is exhausted. The 
wet garments come in contact with the skin, and the 
moisture is absorbed. 

This (6) gives the eye an opportunity 
?. f tl 1 l ^f"! e ^" to aid the mind in comprehending the 

tinal \ llli (6). f & 

outer structure of the villi. The vein 
capillaries which take up the digested food are here 
shown. 



102 ELEMENTARY PHYSIOLOGY. 

Number (7) gives us a view of the 

thl ]Lun S sT7) structure of tlie l^ngs. As you know, 
the lungs are composed chiefly of cells 
in which the impurities are exchanged for fresh 
supplies of life-giving oxygen. Here these cells and 
blood-capillaries are seen. 
^ .,, . The parotid, the principal one of the 

Capillaries of r . 

the Parotid salivary glands, is also composed mostly 

Brain (9) and °^ a capillary net-work, as shown here 
cellular (8). At (9) we see the capillaries of 

Tissue (lO). \ , . . , -, n -, • t 

the brain, with red and white corpuscles, 
or blood-discs, passing through them, carrying 
nourishment to the brain. 

(10) shows how cells grow in length and then 
split into tissue-forming fibers. The cell, you will 
remember, is the smallest possible part of the body, 
and is the most important structure of the system, 
since all tissues and organs are made up of cells, just 
as sandstone is made up of millions of small grains 
of sand. But sand is lifeless, while, in the living 
body, life resides in the cell. 

Under the microscope the muscular 

Elastic Tis- 

sues (ii), nius- fiber has the appearance as shown at 
cuiar Fiber m 2 ). It consists, of course, of many 

(12), and Bone- v J ' ' J 

Corpuscles cells joined together, as will be seen 
by carefully examining this cut. The 
structure of the bones, with their canals and little 
lakes, through which their nourishment is carried, is 
nicely shown at (13). Examine it carefully, and 
then procure, if possible, a bone cut crosswise, and 
compare. 



LESSONS FROM THE MICROSCOPE. 103 

voluntary We nave seen that voluntary muscles 
Muscles (14). are made up of bundles of fibers. This 
is beautifully shown here. We also see the cross- 
markings, or sirice, which is a peculiarity of volun- 
tary muscles. An examination of a piece of cooked 
beef will be helpful in connection with this view. 

The all-important gastric juice, so much 

stomaciuis? neec ^ e( ^ * n a P ro P er digestion of the 
food, is secreted by glands of the 
stomach wall. Such a gland is here represented in 
a very admirable manner. From the little mouths 
here seen, exudes the gastric fluid during the pro- 
cess of digestion. 

At (16) and (17) are representations of 

Xerve -fibers v J x J L 

of Brain (16), nerve-fibers of the brain. Their healthy 
action, the abundance of their cells and 
their proper nourishment largely determine our 
mental capabilities. 

The hepatic or liver vein, by which 
through He- ^e t>loocl is collected and carried from 
paticveiti(i8).the liver toward the heart, is here 
shown as passing through the adjacent liver sub- 
stance. The meshes of the liver capillaries are also 
seen. In these the bile is secreted. 

The microscopic appearance of the 
structure^*)), structure of the kidneys is here repre- 
sented (19). The peculiar little cap- 
sules or balls, called Malpighian Corpuscles, are a 
part of the mysterious organism provided for the 
secretion of the urea from the blood. 



104 ELEMENTARY PHYSIOLOGY. 

Fig. (20) shows the red corpuscles 

Red Blood- & \ J r 

Corpuscles of the blood of different animals. 
Blood consists of a countless number 
of solid bodies floating in a liquid. Some of these 
solids are of a red color, while others are pale or 
white. These solids are called corpuscles or blood- 
discs. They vary also in shape in different ani- 
mals. In man, the discs are usually nearly or quite 
circular, though, when seen in different positions, 
they present different appearances; just as a coin, 
looked at perpendicularly to its surface, looks cir- 
cular, and, when we look at it edgewise, seems of 
an entirely* different shape. These wonderful little 
bodies are so small that, of the red discs, 3,500, laid 
side by side, would measure only an inch, and, if 
placed one upon another, 18,000 would be required 
to make a column of that height. They usually 
arrange themselves in piles, and fit in each other 
like so many saucers or butter plates. It is the 
great number of these corpuscles which gives blood 
its color. 

The structure of the strong tendons by 
«^ nd ^ US which the muscles are attached to the 

liber (21) ; 

Adipose Tis- bones, is shown very plainly at (21,. 
As will be seen here they consist of 
many longitudinal fibers. Number (22) shows us 
how adipose cells appear under the microscope 
(23), and gives us another view of the structure of 
the bones. This is from the ulna of the forearm. 



LESSONS FROM THE MICROSCOPE. 105 

. The mucous membrane lining the 
Epithelial mouth, nose and other cavities com- 

Cells (584) ; 

Cells of Kpi- ruunicating with the outside, is covered 
eniii* ( ). w ^^ ce jj g ca ]_j e( j e pith e li a l cells. Here, 

at (24) we have a magnified view of these cells from 
the mouth; at (25) we see, as through a micro- 
scope, the cells of the epidermis. Though the worn- 
out particles of the cr.ticle can be seen with the 
naked eye, their peculiar structure can not be thus 
perceived. 

The choroid coat of the eye is of a 

Pigment froni ^ 

Choroid coat dark color, and absorbs the superflu- 
5e ous light brought into the eye. Its 

color is due to a dark pigment consisting of regu- 
larly formed six-sided cells. Their shape is seen 
at (26). 

The bile is secreted in the liver cells, 

Other Views • • p i • i • 

(27) to (3i), a microscopic view or which is given 
us at (28). 

Each of the thirty-one pairs of spinal nerves has 
two branches, as seen from (29). The posterior 
root has a ganglion of nerve matter which has the 
pow r er of originating motion. (30 and (31) show 
us how the different nerve-cells appear when seen 
through the microscope. 

Thus we have afforded us a series of views by a 
careful study of which we may be led to appreciate 
the fact that we are "fearfully and wonderfully 
made." 



EFFECTS OF ALCOHOL. 



The principal organs of the body, and 
value of a the functions of each, are now quite 

Sound Body. ' ^ 

familiar to us. Let us now consider 
briefly the necessity of guarding against anything 
and everything which would in any way impair the 
health of these organs, or interfere with them in the 
performance of their work. 

If a grain of sand should find its way into the 
eye, inflammation would at once result; sight, the 
function of the eye, would be interrupted. If, on 
account of some disease, the muscles of the heart 
should cease to contract and expand with their 
ordinary regularity, or stop their action entirely, 
the blood would cease to circulate and life would end. 
Thus, the well-being of the body, yea, life itself, 
depends upon the healthy action of the various 
organs which are our servants in our body-house. 

Does it not seem strange, then, that so 
Abuse of the man y thousands should still persist in 

abusing their bodies, w r hich are made 
"in the image of their Creator"? Yet there are 
such who willfully take into their systems that 
which not only interferes with the healthy action of 
their bodily organs, but leads to certain death. More 
than this, they injure not only their bodies, but 
destroy their mental faculties, dethrone reason, 
bring misery and woe upon their families, and fail 
to accomplish life's ends. 



EFFECTS OF ALCOHOL. 107 

. What is strong drink? It is a liquid 
strong Drtnk. w j lic j a con t a ins alcohol in large or small 
quantity; and, if taken into the system, will affect, 
more or less, all the organs and tissues of the body; 
and, if the quantity is sufficient, will cause what is 
called drunkenness or intoxication. 

It is a liquid which in appearance can 

Alcohol, and , -, -,. ,. . -, -, « , TJ » 

What is it? n °t be distinguished trom water. It 
one vial be filled with water and an- 
other with alcohol, at a little distance it cannot be 
told which contains the water and which the alcohol. 
But the properties of the two are remarkably dif- 
ferent. The alcohol has a strong odor, and a hot, 
biting taste. A small quantity may be placed in a 
shallow dish and a burning match held to it, when 
it wiil readily burn with a pale flame, but giving 
off much heat. If the white (albumen) of an egg 
be put in a cup, and alcohol poured on it, the albu- 
men will soon become white, hard and tough, as if 
cooked. In all these and in many other particulars, 
it differs very much from water, which it so much 
resembles in appearance. 

Nearly all of the grains, as wheat, rye, 

What Is Its ii i , . i 

Origin? barley, corn and rice, contain much 

starch. Corn-starch is made from corn, 
and sold by the grocer. The starch of these grains 
can, under certain circumstances, be converted into 
sugar, and this, in turn, can be changed into two 
very different substances, carbonic acid gas and 



108 ELEMENTARY PHYSIOLOGY. 

alcohol. Thus alcohol may be made from many sub 
stances. The juices of all fruits contain the sugar 
from which it may be produced. From the grape, 
currant, blackberry, elderberry and cherry, wine 
is made; from apples, cider is pressed; whisky is 
made from corn, barley, rye and other grains; rum 
is made from molasses and sugar cane. All of 
these contain alcohol in different quantities. 

If you take an apple and squeeze out 

i>one? S °^ ^ ^ e j u i ce > y ou w iH have cider. 

If this is allowed to stand in the 
warm open air, it will very soon begin to change its 
nature. If watched closely, small bubbles will be 
seen rising to the top and escaping. These are bub- 
bles of carbonic acid gas, one of the products of the 
change of the fruit-sugar. The other is alcohol, 
which mixes with the liquid. The cider is now no 
longer sweet, but contains alcohol, is properly called 
"hard cider," and is a dangerous drink. It is 
the escaping gas that makes cider sparkle, and 
beer foam. 

The change of the cider, from sweet to 

Fermentation. hard? Qr frQm the harml ^ s j uice Q f tlie 

apple to that containing alcohol, is called fermenta- 
tion. All alcohol is the result of the fermentation 
of sugar, or some substance containing sugar. The 
apple juice, as soon as exposed to the warm atmos- 
phere, absorbs from the air a peculiar substance 
called a ferment^ which is something like yeast. It 



EFFECTS OF ALCOHOL. 109 

at once begins to " worK," that is, it begins to change 
the sugar to carbonic acid gas and alcohol. Thus 
wine is made from grapes, currants and other fruits. 
This kind of fermentation is called vinous fermenta- 
tion. 

If the process of fermentation is allowed 
Acetous ^ Q continue, the hard cider and the fer- 

Fer mentation. ' 

mented wine will again change their 
nature. If a barrel containing cider is left in 
the warm sun, with an open bung (why), it first 
changes its sugar into alcohol. Additional ferment 
will change the alcohol of the hard cider to acetic 
acid, or cider-vinegar. This is called acetous fer- 
mentation. 



Beer brewers add water to barley, 

Barley. 



and keep it sufficiently warm to cause 



it to sprout, when the starch it contains 
will change to sugar. More heat is added, and the 
germs or young sprouts are killed, and the water 
evaporated. This is now called malt, which is 
soaked in water, the sugar which it contains is dis- 
solved and the sweet liquid drained off. Yeast is 
added to this liquid, to start the process of fermen- 
tation, or change of sugar to carbonic acid gas and 
alcohol. It is now called beer. 

If a cold cup be inverted and held 

over the spout of a tea-kettle from 

which steam is escaping, the steam will be condensed 

and gather in drops on the inner surface of the cup. 



110 ELEMENT AR Y PHYSIOLOGY. 

The water is first changed to vapor and this in 
turn is condensed to a liquid again. This is called 
distillation. 

Now, if a quantity of wine or hard cider be 
placed in a vessel with an opening something like 
the spout of a tea-kettle, and heat applied, distilla- 
tion will take place. But alcohol will boil, that is, 
change to vapor, at a temperature of 173°, while 
water requires 212°. Hence, the alcohol will be 
vaporized and pass off as steam before the watery- 
portions will have reached a sufficient temperature. 
Thus, the vapor of alcohol can be condensed and 
collected as almost or quite pure alcohol. But suffi- 
cient heat may be applied to drive off some of the 
water with the alcohol. When about as much water 
is driven off as alcohol, the result of the process of 
distillation is brandy, ivhisky or rum. 

Thus, we have seen that there are 

Two Classes 

of strong two kinds, or classes, of strong drink, 

the pernicious element in each being 

alcohol. One kind is called fermented liquors, such 

as wine, beer, ale and cider, and contain from three 

to twenty per cent, of alcohol. The other kind is 

known as distilled liquors, rum, whisky and brandy, 

containing as high as fifty-five per cent, of alcohol. 

An appetite for these liquors is the cause of more 

poverty, unhappiness, wickedness and crime than all 

other causes combined. We will now consider their 

effects upon the human system, 



EFFECTS OF ALCOHOL. Ill 

EFFECTS ON THE DIGESTIVE SYSTEM. 

To possess a healthy digestion is a 
^ Heal * hy great blessing. It is essential to our 

stomach. o r> 

physical well-being. Here we have a 
fine representation of a healthy stomach and liver. 
(See Aid.) The liver naturally lies across the 
stomach, but here it is turned up to show us the 
healthy appearance of a stomach which has never 
been abused by that terrible destroyer, alcohol. 

If taken in an undiluted form, alcohol 
'would burn the mouth and throat. The 
stomach would suffer in a similar way. But in its 
most diluted form it has an irritating effect upon 
the lining membrane of the stomach and intestines. 
Inflammation tells the story of the unnatural condi- 
tion of things. The gastric juice becomes thick and 
unfit for its work in the digestive process. The 
constant inflammation indicates unnatural heat, and 
an unnatural thirst ensues, which is the probable 
reason for the fact that the more liquor a man drinks 
the more he wants. The quantity he drinks to-day 
will not satisfy him to-morrow, since more and more 
will be needed to counteract the ever-increasing 
inflammation. 

This second cut shows us plainly the early stages 
of inflammation. It represents, perhaps, the stomach 
of one who has had his first experience with the 
deadly staff; and yet how different in appearance 
from the stomach represented above, 



112 ELEMENTARY PR YSIOLOGY 

At the bottom of this chart we see a 
Ulceration. more advanced stage of the difficulty. 
The blood-vessels are very much dilated, and indi- 
cate that extraordinary work has devolved upon this 
organ. The blood-vessels seem to have lost their 
power to contract sufficiently to expel the increased 
amount of blood brought hither. And here we see 
the results (first cut, next chart), of long continued 
distension of the blood-vessels. They have broken 
and sores or ulcers are the result. The stomach is 
now no longer able to perform its functions; the 
food is no longer properly digested, and as a con- 
sequence the blood is impoverished, and the general 
health has failed. All on account of the drink-habit 
which has now become so firmly fixed upon its victim 
that it is almost beyond human effort to break loose 
from it. 

The faithful servant of the body, the 

L<ast Stages m J 

of Aicoiioi stomach, tries, from the first, to adapt 
itself to the derangements caused by 
the use of alcohol as a beverage. Just as the cuti- 
cle of the hand thickens and hardens, when we use 
an ax or shovel, so the stomach, if it is constantly 
being irritated by the presence of alcohol, becomes 
thick, tough and unnatural; and consequently 
becomes better adapted for the purpose of a whisky 
jug, but less for the purpose for which it was 
intended to digest food. The blood vessels of the 
stomach, having been dilated to their utmost, their 
diseased walls give way and ugly ulcers are formed. 



THE EFFECTS OF ALCOHOL. 113 

These canker-like eruptions seen here, first eat 
through the inner coat, then the outer is attacked 
and the painful sores cause great suffering. Ulti- 
mately it can no longer accommodate itself to the 
condition of things. It gives up in despair. It can 
no longer retain and much less digest food. Its con- 
dition and appearance is shown here on the chart. 
A long and painful disease follows, and at last death 
relieves the poor slave to appetite. 

Let us observe right here, how gradual is the pro- 
cess. How small and seemingly insignificant the 
beginning. And yet how certainly does the gratifi- 
cation of one thirst create the next. We would all do 
well to accept as our motto: " Touch not, taste not, 
handle not." 

We have just seen how alarming is the 
theViver* 1 effect of alcohol on the stomach. But 
the liver, the healthy action of which 
we have found so necessary in the food-preparing 
and blood-purifying processes, suffers fully as much 
from the use of alcoholic drinks. 

It is probable that most of the alcohol taken into 
the stomach is there absorbed and carried directly 
to the liver without passing into the intestines. A 
proper secretion of the bile in the liver demands that 
the cellular structure of that organ remain un- 
changed. Alcohol causes a change of these cells to 
fatty tissue, and an enlargement of the organ follows. 
Its tissues then become lumpy or knobbed, and pro- 
duces what is known as "gin, or hobnailed liver" 



114 ELEMENTARY PHYSIOLOGY. 

Let us compare its appearance under such conditions 
as we have it here represented, with its looks when 
in health, as seen on a previous plate. 

What is the result of a liver thus dis- 
eased? The answer is two-fold: First, 
the bile and liver sugar are not properly taken from 
the blood, and whatever poisonous matter may be 
contained in the blood which should be removed 
with the bile must remain in the system, and will 
certainly prove destructive to health. In the second 
place, the digestive process is not furnished with 
the needed bile, and the work of preparing the food 
will be imperfectly performed. 

The effect of a continued use of alcohol 
the^idneys. u P on the kidneys is much like that 
upon the liver. In the kidneys the 
blood is constantly being filtered, and the poisonous 
urea is being taken from it and expelled from the 
body. If the blood carries alcohol into the cells of 
these organs they will be irritated, inflamed, and 
sometimes destroyed. This is known as Brightfs 
disease, though other causes may lead to the same 
difficulties and terminate in the same disease. Here 
we have a view of a very common derangement with 
drinkers. It is an accumulation of fat about the 
kidneys, and may prove fatal. 

EFFECTS ON TEE NERVOUS SYSTEM. 

Medical authorities tell us that after 

On the Brain, n -i , -, £ -, -i -, . -i i 

the death or a hard drinker, more alco- 
hol is found in the tissues of the various parts of 



THE EFFECTS OF ALCOHOL. 115 

the nervous system than any other part of the body. 
It has been found in sufficient quantities in the brain 
to distill it from the brain tissue. Its abundance in 
the nervous tissue is probably due to the amount of 
water which nerve tissue contains, and for which 
alcohol has a remarkable affinity or greed. As stated 
elsewhere, if alcohol is poured in a cup contain- 
ing the white of an egg , it will harden or coagulate 
it. The tissue of the brain is similarly affected and 
made less sensitive. This loss of feeling is called 
paralysis. It also causes inflammation as seen here 
in the first plate of this chart. Compare the appear- 
ance of the two hemispheres of this important 
organ, one side represents the brain in health and 
the other as affected by strong drink. 

THE BRAIN IS THE SEAT OT THE MIND. 

If alcohol effects its tissues as we have 
onsequences. i earne( j ^ n j^q preceding topic, we may 

understand to some extent at least, how the habitual 
use of alcoholic drinks causes temporary insanity; 
and men are made silly in their actions, boastful in 
conversation and unmanly in every respect. That 
part of the brain which controls the voluntary mus- 
cles shows the effects of stimulants very promptly. 
The hand trembles and shakes "like a leaf." Walk- 
ing soon becomes a difficult task. The control of 
the lips is lost and a quivering is the result. The 
tongue becomes ungovernable, and the poor toper 
becomes an object of pity, as he staggers through 



116 ELEMENTARY PHYSIOLOGY. 

the streets no longer a man, but a poor, degraded 
wretch, made so by his appetite for drink. 

The effect of alcohol upon the brain 

Alcoholic .. - c j. ' ip • i 

Softening of sometimes manitests mselt m a degen- 
the Brain. eration of the brain tisssue. Fat accu- 
mulates as a result of frequent intoxications and 
the result is known as alcoholic softening, and the 
appearance of the brain in such condition is showp 
by the plate. 

The last cut of the stomach on the tem- 
Tremens! perance charts gave us a view of that 

organ of a patient suffering from de- 
lirium tremens. The Aid furnishes us a correspond- 
ing view of the brain of such a patient. It is usually 
supposed that this condition is reached only after 
years of dissipation and drunkenness. Ordinarily this 
is true. But reliable medical authorities affirm that 
persons of a particularly nervous disposition are 
sometimes attacked by this terrible malady when but 
small quantities of intoxicants are taken. Those 
who indulge in strong drink are never absolutely 
safe. It may attack them at any time. 

The victim of delirium tremens is in terrible fear 
and anxiety. His mind is so completely disturbed 
and his imagination so thoroughly aroused as to 
cause him to think his best friends enemies who 
would do him harm. He sees horrible sights and 
hears noises which alarm him. In his awful con- 
dition he raves and tears, cutting, tearing and biting 
himself like a madman; and not unfrequently dies 



THE EFFECTS OF ALCOHOL. 117 

and thus escapes from his agony. Oh, that human 
beings should so abuse themselves as to bring them- 
selves into such a condition ! 

The same paralyzing effect of alcohol 

Effect on the n i • j» i • i i x. • 

serves. on ^ ie k raia or which we made mention 

in the preceding topics, is noticeable 
in the nerves. The alcohol takes up the moisture 
in the nerve tissues, leaving them more or less inca- 
pable of transmitting sensation. There is on record 
an account of a man, who, in his drunken stupor, 
burned his foot almost to a cri&p without becoming 
conscious enough to remove it from the camp fire 
into which he had unconsciously placed it. The 
nerves were so thoroughly paralyzed by alcohol as 
to fail to transmit sensation to the brain, even if 
that organ had been in a fit condition to receive the 
intelligence. The brain and nerve tissues are 
among the first substances of the body to become 
affected by alcohol. 

The effect of alcohol on the heart is 
different Ef- more or } esg indirect. It is through 

fectsof Intox- ° 

icants Upon the affected nerves that its effect upon 
the heart and circulation is brought 
about. The action of the heart is governed by the 
nerves, which act as a sort of brake, thus preventing 
a too violent action. Now when these nerves be- 
come affected and lose their control of the heart's 
action, it will beat more rapidly, and also with 
greater force. Thus the strain upon the heart is 
greatly increased, while the intervals of rest be- 



118 ELEMENTARY PHYSIOLOGY. 

tween the beats is diminished, which must be injuri- 
ous to that important organ. With the increased 
activity of the heart, comes an increased rapidity 
of the flow of blood through the blood-vessels- 
The blood is forced to the surface, which becomes 
flushed, and, if long continued, the blood-capillaries 
at the surface lose their power of contraction, and 
the drunkard's nose is the result. 

As in the kidneys, the tissue of the heart-walls 
will degenerate and change to fat. A fatty coat 
may run back from about it, and it is known as fatty 
accumulation. If the use of alcohol is continued, 
the heart will finally succumb; its fibers will become 
relaxed, its cavities become enlarged, it will entirely 
lose its power to contract, and death will ensue from 
paralysis of the heart 

Sometimes the heart continues its efforts to expel 
the blood, even when the cavities have increased 
their capacity, and the walls become thin and weak. 
Alcoholic rupture is then likely to occur. The effect 
on the appearance of the nerves, eye and blood- 
vessels is shown on the Aid. 

Without going farther into the details 
Synopsis. Q f a ] co hol, and other effects upon the 
human system just mentioned in these lessons, let 
us recall briefly what it will not do, and then resolve 
never to use it except as a medicine, and then only 
when directed to do so by a competent physician. 
Following are a few of the many facts concerning 
alcohol, which have so frequently been demonstrated 



TEE EFFECTS OF ALCOHOL. 119 

as to be no longer questioned: 

WHAT IT WILL NOT DO. 

1. Alcohol is not a food, hence — 

2. It will not nourish the system. 

3. It is not assimilated and made a part of the 
body tissue. 

4. It will not fortify against cold. 

5. It will not quench thirst. 

6. It will not increase our powers of endurance. 

7. It will not make the nerves more steady. 

8. Its use will not make us more manly. 

9. It will not increase our mental powers. 

10. It will in no way benefit the system, except 
as a prescribed medicine. 

11. It will not prolong life. 

12. Its use can in no way add to our good name 
or reputation. 

TOBACCO AND ITS EFFECTS. 

The use of tobacco is so prevalent that all know 
what it is. Like alcohol, it does little or nothing for 
which its use can be recommended, while, on the 
other hand, there are many reasons for which its use 
should be entirely avoided. 

It contains a substance called nicotine, 
Poison ° IS * w ^ c ^ * s a deadly poison. This poison 

can be extracted from the leaves of the 
tobacco plant, and is a dark-colored liquid of a 
sharp, biting taste. It has been found that a few 



120 ELEMENTARY PHYSIOLOGY. 

drops of this poison, placed on the tongue of a dog, 
will cause death. This nicotine, extracted from the 
tobacco and evaporated, forms large parts of the 
crust in the bowl of an old tobacco pipe. 

Its use is unnatural. When first at- 
Its Effects tempted, it causes nausea and nervous 
Young. and muscular weakness. It is a well- 

known fact that it exerts a very perni- 
cious influence, particularly upon the young. It 
prevents their physical and mental development; it 
stunts their growth, and paves the way for disease 
in after years. 

Injurious as tobacco smoking (in its 
Smoking. common form) may be, smoking cigar- 
ettes is even more so. The poorest 
kind of tobacco is often used in making them, and 
poisonous substances are added to give them the 
proper strength and flavor. Opium, which is used 
in considerable quantities in this adulteration, is 
carried with the smoke to the lungs. Nicotine, that 
deadly poison found in tobacco, aids in the poison- 
ing process. In view of the detrimental effect of 
cigarettes, it is not surprising that a number of 
States have enacted laws prohibiting the sale of 
cigarettes to young boys. 

To show you that the mucous lining of 

An Expert- L1 ii i • i 

ment. ™ e m °uth and air passages is sub- 

jected to a sort of tanning process, and 
thus has its ordinary functions impaired by cigar- 
ette smoking, a simple experiment may be per- 



TOBACCO AND ITS EFFECTS. 121 

formed. If we take a clean white cloth or handker- 
chief, two or three double, and inhale the smoke of 
a lighted cigarette, and then force it from the mouth 
through the cloth, a brownish yellow spot or stain 
will be found on it, which consists of the poisonous 
nicotine and other ingredients contained in the 
smoke, and mixed with the moisture of the mouth. 
Deposits of this kind are made upon the walls of the 
air passages when cigarettes are smoked, which 
must be injurious. 

The respiratory organs suffer the most 
The Respira- f rom cigarette smoking. We have here 

tory Organs. 7 . . 

How Affected. (See Aid.) a series of views which will 
help us to understand the nature of the 
harm done, and, by a careful study of these, we may, 
perhaps, all be led to the resolve never to smoke 
cigarettes or cigars. 

The trachea, or wind-pipe, in health has the 
appearance shown at 1 and 2; 4 shows us how 
it looks inside, and 3 outside, when it has become 
inflamed and irritated by the use of cigarettes. The 
inner structure of the lungs, with its subdivisions 
of the bronchial tubes and air-cells, in health, is 
nicely represented at 5. Here also we see the 
plump, full, well-formed lung before it has become 
shriveled up by the contents of the cigarette smoke. 
At 6 Ave see the effects. The air cells are filled 
up, and the bronchial subdivisions are almost 
wholly obstructed by nicotine deposits. 

How, then, can the blood -purifying process be 



122 ELEMENTARY PHYSIOLOGY. 

successfully carried on in such a lung as is here 
represented? 

Here in the lower right-hand corner of this plate 
we have a view of what is left of the lung after years 
of cigarette smoking. Nicotine has filled every air- 
cell. Nicotine had caused his death. 

In the opposite lower corner on the Aid is seen 
a view of what is called smoker's cancer. It usually 
occurs in the throat and often proves fatal. 

We have now briefly considered the 

Conclusion. ,. -, £ . ,-, , , £ 

essential reatures m the structure or 
the human body and the principal functions of tbe 
various organs. What is beneficial, as well as what 
is harmful, in its effects, has received attention. 
With the assistance of the Anatomical Aid, we have 
endeavored to impress the mind with some of the 
effects of alcohol and tobacco. If now, by the use 
of this little book in connection with the Aid, our 
young people may be induced to study the wonder- 
ful mechanism of their bodies, and try to avoid that 
which is injurious or in any way interferes with 
their physical or mental well-being, we shall have 
accomplished our purpose. 



APPENDIX. 



INDEX 

TO THE 

COMPLETE NERVOUS SYSTEM. 



I. THE CEANIAL AND SPINAL SYSTEM. 



No. Common Name. 

1 Brain. 

2 Small Brain. 

3 Tree of Life, 

4 Varol's Bridge. 

5 Three fold Nerve. 

6 Abducent Nerve. 

7 Face and Sound Nerve. 

8 Tongue and Pharynx Nerve, 

9 Willis' Accessory Nerve. 

10 Loose cavity containing lung 

and stomach nerve ducts. 

11 Lower tongue nerve. 

12 Descending branches hypo- 

glossal nerves. 

13 Cranial portion of the Spinal 

Cord. 

14 Decussate pyramid. 

15 Part of cervical spinal cord. 



Latin or Professional Name. 
Cerebrum. 
Cerebellum. 
Arbor vitas. 
Pons Varolii. 
Nervus Trigeminus. 
Nervus abducens. 
Nervus facialis et acousti- 

cus. 
Nervus glosso-pharyngeus, 

vagus et accessorius. 
Nervus accessorius Willisii. 
Nervus vagus pneumo-gas- 

tricus. 
Nervus hypoglossus. 
Kami descendens nervi hypo- 

glossi. 
Medulla oblongata. 

Decussatio pyramidum. 
Pars cervicalis medullas spi- 
nalis. 



11 



APPENDIX. 



No. Common Name. 

16 Part of thoracic spinal cord. 

17 Bulbous expansion at 

end of spinal cord. 

18 Terminal threads, spinal 

cord, 

19 Neck nerves 1. 

20 Neck nerves 8. 

21 Network of neck nerves. 

22 Network of arm nerves. 

23 Back bone nerve 1. 

24 Back bone nerve 2. 

25 Nerves between ribs. 

26 Loin nerve 1. 

27 Loin nerve 5. 

28 Network of loin nerves. 

29 Anterior crural nerve. 

30 Hip — abdominal nerve. 



31 Hip — groin nerve. 

32 Groin skin nerve. 

33 Obturator nerve. 

34 Sacral nerve 1. 

35 Sacral nerve 5. 

36 Network of sacral nerves. 

37 Coccyx nerves. 

38 Sympathetic nerve. 

39 Upper cervical ganglion. 

40 Middle cervical ganglion. 

41 Lower cervical ganglion. 

42 Thoracic ganglia. 

43 Loin ganglia. 

44 Sacral ganglia. 

45 Coccyx ganglion. 

46 Connecting branches be- 

tween sacral and sympa- 
thetic nerves. 



Latin or Professional Name. 
Pars thoracica medullae spi- 
nalis. 



Filum terminale. 

Nervus eervicalis 1. 

Nervus eervicalis 8. 

Plexus eervicalis. 

Plexus brachialis. 

Nervus dorsalis 1. 

Nervus dorsalis 2. 

Nervi intercostales. 

Nervus lumbalis 1. 

Nervus lumbalis 5. 

Plexus lumbalis. 

Nervus cruralis anterior. 

Nervus ilio — hypogas tri- 
cus (ramus exterior et in- 
terior). 

Nervus ilio inguinalis. 

Nervus inguino cutaneous. 

Nervus obturatorius. 

Nervus sacralis 1. 

Nervus sacralis 5. 

Plexus sacralis. 

Nervi coccygei. 

Nervus sympaticus. 

Ganglion cervicale superior. 

Ganglion cervicale medium. 

Ganglion cervicale inferior. 

Ganglia thoracica. 

Ganglia lumbalia. 

Ganglia sacralia. 

Ganglion coccygeum. 



NERVOUS SYSTEM. 



ill 



No. Common Name. 

47 Sciatic nerve (Hip nerve). 

48 Groin nerve. 

49 Shoulder bone nerves. 

50 Branches of skin and axle 

nerves. 

51 Arm skin nerves, internal 

posterior. 

52 Arm skin nerve, small in- 

ternal. 

53 Branches middle skin nerves 

(arm). 

54 Middle arm skin nerve. 

55 Branches skin palm nerves of 

middle skin nerve. 

56 Branches of middle under 

skin nerve over ulna. 

57 Branches under skin nerves, 

overlying cutaneous mus- 
cle. 

58 Eadial nerve branches. 

59 Voluntary ulna nerve. 

60 Voluntary finger nerves. 

61 Network of arm pit nerves. 

62 Middle nerve, sending 

branches to thumb, index 
and middle finger and 
radial side of ring finger. 

63 Ulna nerve. 

64 Voluntary ulna nerve, 

65 Spiral muscular nerve lying 

against radius. 

66 External elbow joint nerve. 

67 Superficial radial nerve. 

68 Musculo cutaneus nerve. 

69 Anterior leg nerve. 

70 External anterior femoral 

nerve. 



Latin or Professional Name. 

Nervus ischiadicus. 

Nervus inguinalis. 

Nervi supraclaviculars. 

Rami cutaneus et nervi ax- 
illaris. 

Nervi outaue us brachii, in- 
ternus posterior. 

Nervi cutaneus brachii inter- 
nus (minor). 

Ramus nervi cutanei medii. 

Nervus cutaneus brachii 
medius v. internus major. 

Ramus cutaneus palmaris, 
nerv. cutan. medii. 

Ramus cutaneus ulnaris 
nerv. cutan. medii. 

Ramus cutaneous nerv. mus- 
culo cutanei. 

Ramus nervi radiales. 
Nervus ulnaris volaris. 
Nervus digitales volaris. 
Plexus axillaris (brachialis). 
Nervus medianus. 



Nervus ulnaris. 
Nervus ulnaris volaris. 
Nervus musculo — spiralus v. 

radialis. 
Nervus interosseus externus. 
Nervus radialis superficialis. 
Nervus musculo— cutaneus. 
Nervus cruralis anterior. 
Nervus cutaneus femoris 

anterior externa. 



IV 



APPENDIX. 



No. 
71 

72 
73 

74 

75 



76 

77 
78 

79 

80 



Common Name. 
Groin nerve. 
Groin skin nerve. 
Large saphenic nerve. 
Middle anterior femoral 

nerve. 
Internal anterior femoral 

nerve lying against small 

saphenic. 
Branches of hip abdominal 

nerves. 
Branches hip groin nerves. 
Branches muscular leg 

nerves. 
Superficial peroneal nerve 

fibular. 
Internal foot skin nerve. 



81 Middle foot skin nerve. 



82 External leg skin nerve. 



83 



84 



85 



86 



87 



90 
91 
92 
93 
94 
95 



Deep peroneal or fibular 

nerve. 
Deep branch of peroneal 

nerve. 
External branch of peroneal 

nerve. 
Cervical or neck back bone 

joint. 
Back bone joint (1). 
Back bone joint (12). 
Loin back bone joint (1). 
Loin back bone joint (2). 
Sacrum bone. 
Coccyx bone. 
First rib. 
Last rib. 
Crest of ilium bone. 



Latin or Professional Name. 

Nervus inguinalis. 

Nervus inguino cutaneus. 

Nervus saphenus major. 

Nervus cutaneus femoris 
anterior medius. 

Nervus cutaneus femoris 
anterior internus v. saphe- 
nus minor. 

Kami nervi ilio hipogastrici. 

Rami nervi ilio inguinalis. 
Rami musculares nervi cru- 

ralis. 
Nervus peronseus superfi- 

cialis, con. 
Nervus cutaneus dorsi pedis 

internus, et. 
Nervus cutaneus dorsi pedis 

medius. 
Nervus cutaneus cruris 

externus. 
Nervus peronseus profundus. 

Ramus internus peronseus 

profundus. 
Ramus externus peronseus 

profundus. 
"Vertebra cervici (7). 

Vertebra dorsi (1). 
Vertebra dorsi (12). 
Vertebra lumbalis (1). 
Vertebra lumbalis (2). 
Os sacrum. 
Os coccygi. 
Costa prima. 
Costa termina. 
Crista ossis ilii. 



NERVOUS SYSTEM. v 

No. Common Name. Latin or Professional Name. 

96 Underlying collar muscle Musculus sterno — cleido 

connecting with dternum. mastoidens. 

97 Front scalene muscle. Musculus scalenus anticus. 

98 Middle scalene muscle. Musculus scalenus medins. 

99 Internal intercostal muscles. Musculi intercostales inter- 



100 External intercostal mus- 

cles. 

101 Square loin muscle. 

102 Large loin muscle. 

103 Internal iliacal muscle. 

104 Deltoid muscle (shoulder). 

105 Large breast muscle. 

106 Flexible forearm muscle. 

107 Fold in forearm. 

108 Head of ulna. 

109 Aponeuroses of the palm. 

110 Fleshy ball of thumb. 

111 Short palm muscle. 

112 Cephalic vein (arm). 

113 Basilical vein. 

114 Middle basilical vein. 

115 Middle cephalic vein. 

116 Head of humeris bone. 

117 Sharp process of scapula. 

118 Deltoid muscle. 

119 See No. 105. 

120 Small breast muscle. 

121 Flexible muscle of biceps. 

122 Short head of biceps muscle. 

123 Long head of biceps muscle. 

124 Coracoid arm muscle. 

125 Internal arm muscle. 



Musculi intercostales exter- 

ni. 
Musculus quadratus lumbo- 

rum. 
Musculus psoas major. 
Musculus iliacus internus. 
Musculus deltoideus. 
Musculus pectoralis major. 
Musculus biceps flexon cub- 

iti. 
Plica cubiti. 
Caput ulnae. 
Aponeurosis palmaris. 

Musculus palmaris brevis. 
Vena cephalica brachii. 
Vena basilica. 
Vena mediana basilica. 
Vena mediana cephalica. 
Caput ossis humeri. 
Processus coracoideus. 
Musculus deltoideus. 

Musculus pectoralis minor. 

Musculus biceps flexor cub- 
iti. 

Caput breve, musculus bici- 
pitis. 

Caput longum, musculus bi- 
cipitis. 

Musculus coraco-brachialis. 

Musculus interna brachialis, 



VI 



APPENDIX. 



No. Common Name. 

126 Internal head of extending 

triceps muscle. 

127 Long head of extending tri- 

ceps muscle. 

128 Muscle, serving * to turn 

palm of hand upwards. 

129 Muscle, long, round extend- 

ing wrist. 

130 Muscle, serving to turn 

palm of hand downward. 

131 Eound wrist muscle bend- 

ing or turning. 

132 Short, like functions as 128. 

133 Common bending finger 

muscles. 

134 One of the wrist bending 

muscles. 

135 Long bending striking mus- 

cle. 

136 Muscles serving thumb. 

137 Drawing thumb to the in- 

dex finger. 

138 Shoulder artery. 

139 Arm arteries and veins. 

| . -. ( Arteries and veins of uJna. 

142 Upper anterior spine of 

ilium. 

143 Tailor's muscle. 

144 Middle gluteal muscle (serv- 

ing to turn thigh in and 
outward). 

145 Deep leg stretching muscle. 

146 Straight femoral muscle. 

147 External vastus muscle. 

148 Muscle, serving to bring 

thigh together. 



Latin or Professional Name. 
Caput internum, m. tricipitis 

extensoris. 
Caput longum m. tricipitis 

extensoris. 
Musculus supinator longus. 

Musculus extensor carpi 

radialis longus. 
Musculus pronator teres. 

Musculus flexor carpi radia- 
lis. 

Musculus supinator brevis. 

Musculi flexores, digitorum 
communes. 

Musculus flexor carpi ulna- 
ris. 

Musculus flexor pollicis 
longus. 

Musculus abductor et flexor 
brevis pollicis. 

Musculus abductor pollicis. 

Arteria axillaris. 

Arteriae et venae brachialis. 

Arteriae et venae ulnaris. 

Spina ilii anterior superior. 

Musculus sartorius. 
Musculus glutaeus medius. 



Musculus tensor faciae latae. 
Musculus rectus femoris. 
Musculus vastus externus. 
Musculus pectinaeus. 



XERVOUS SYSTEM. 



Vll 



No. Common Name. 

149 Long drawing muscle. 

150 Large drawing muscle. 

151 Leg muscle. 

152 Internal vastus muscle. 

153 Tendon extending leg. 

154 Knee. 

155 Shin. 

156 Internal / Ankle joint pro- 

157 External ) jections. 

158 Transverse ligament. 

159 Foremost tibial muscle. 

160 Muscle, extending toes and 

foot. 

161 Long peroneal muscle (Fib- 

ula). 



Latin or Professional Name. 
Musculus abductor longus. 
Musculus abductor magnus. 
Musculus cruralis. 
Musculus vastus internus. 
Tendo extensorius cruris. 
Patella. 
Tibia. 

Malleolus internus. 
Malleolus externus. 
Ligamentum transversum. 
Musculus tibialis anticus. 
Musculus extensor digitor- 

um pedis longus. 
Musculus peronaeus longus. 



162 


Short peroneal muscle. 


Musculus peronaeus 


brevis. 


163 


I*ong extending striking 


Musculus extensor 


pollicis 




foot muscle. 


pedis longus. 




164 


Counteracting on 160. 


Musculus extensor 
um pedis brevis. 


digitor- 


165 


Short striking foot muscle. 


Musculus extensor 
pedis brevis. 


pollicis 


166 


Sole muscle. 


Musculus soleus. 




167 


Femoral artery. 


Arteria femoralis. 




168 


Femoral vein. 


Vena femoralis. 




169 


Large saphenic vein. 


Vena saphena magna. 



II. THE SYMPATHETIC SYSTEM. 

DISTRIBUTION OF FACIAL AND PNETJMO GASTRIC 
NERVES. 



1 Descending thoracic aorta. Aorta descendens thoracica. 

2 Innominate artery. Arteria innominata. 

3 I: ght under-shoulder artery, Arteria eubclavia dextra. 



Vlll 



APPENDIX. 



No. Common Name. 

4 Right carotid artery. 

5 Internal carotid artery. 

6 External carotid artery. 

7 Upper thyroid artery. 

8 External jaw artery. 

9 Occipital artery. 

10 Upper ear artery. 

11 Temporal artery. 

12 Pulmonary arteries and 

veins. 

13 Id tercostal arteries and veins. 

14 Descending aorta (abdom- 

inal) with lower aortic 
plexus. 

15 Cceliac artery and plexus. 

16 Kidney artery and plexus. 

17 Upper mesenteric artery 

with plexus. 

18 Lower mesenteric artery 

with plexus. 

19 Common iliacal artery. 

20 Network of upper abdominal 

nerves. 

21 Network of hemorrhoidal 

nerves. 

22 Network of nerves surround- 

ing bladder. 

23 Network of prostate nerves. 

24 Network of lower abdominal 

nerves. 

25 Lower phrenic arteries with 

network of phrenic nerves. 



Latin or Professional Name. 
Arteria carotis communis 

dextra. 
Arteria carotis interna. 
Arteria carotis externa. 
Arteria thyroidea sup. 
Arteria maxillaris externa (v. 

facialis). 
Arteria occipitalis. 
Arteria auricularis superior. 
Arteria temporalis. 
Arteriaeet venae pulmonales. 

Arterise et venae intercostal is 
Aorta descendens abdom- 

inalis, con plexus aorticus 

inferior. 
Arteria coeliaca con plexus 

coeliacus. 
Arteria renalis con plexus 

renalis. 
Arteria mesenterica superior 

con plexus t mesentericus 

sup. 
Arteria mesenterica inferior 

con plexus mesentericus 

inferior. 
Arteria iliaca communis. 
Plexus hypogastricus su- 
perior. 
Plexus haeruorrhoidales. 

Plexus vesicalis. 

Plexus prostaticus. 

Plexus hypogastricus in- 
ferior. 

Arteriae phrenicse inferiores 
con plexus phrenicus. 



NERVOUS SYSTEM. 



IX 



No. Common Name. 

26 Great network of stomach 

nerves. 

27 Splenic artery with network 

of splenic nerves. 

28 Liver artery with network of 

liver nerves. 

29 Upper network with semi- 

lunar ganglion. 

30 Loin ganglion. 

31 Sacral ganglion. 

32 Thoracic gland 1. 

33 Thoracic gland 7. 

34 Large splanchnic nerve. 

35 Small splanchnic nerve. 

36 Upper network of thoracic 

nerves. 

37 Lower ganglion of neck 

nerves. 

38 Middle ganglion of neck 

nerves. 

39 Upper ganglion of neck 

nerves. 

40 Network of nerve molles. 

41 Front ear nerve. 

42 Posterior ear nerve. 

43 Facial nerves and branches 

causing goose flesh on skin. 

44 Small occipital and upper 

ear nerve. 

45 Willis' accessory nerve. 

46 Network of neck nerves. 

47 Vagus nerve. 

48 Recurrent nerve. 

49 Phrenic nerve. 

50 Network of arm nerves. 

51 Network of loin nerves. 
62 Network of sacral nerves. 



Latin or Professional Name. 
Plexus gastricus magnus. 

Arteria splenica con plexus 

splenicus. 
Arteria hepatica con plexus 

hepaticus. 

Plexus Solaris con ganglion 

semi-lunarius. 
Ganglion lum bale. 
Ganglion sacrale. 
Ganglion thoracicum 1. 
Ganglion thoracicum 7. 
Nervus splaDchmcus major. 
Nervus splauchnicus minor. 
Plexus thoracicus superior. 

Ganglion cervicale inferior. 

Ganglion cervicale medina. 

Ganglion cervicale superior. 

Plexus nervorum mollium. 

Nervus auricularis anterior. 

Nervus auricularis posterior. 

Nervus facialis et pes an- 
serius. 

Nervus occipitalis minor e!: 
nervus auricularis supe- 
rior. 

Nervus accessorius Willisii. 

Plexus cervicales. 

Nervus vagus. 

Nervus recurrens. 

Nervus phrenicus. 

Plexus brachialis. 

Plexus lumbalis. 

Plexus sacralis. 



APPENDIX. 



No. Common Name. 

53 Nerves between ribs (inter- 

costal. 

54 Network of nerves of the 

gullet (oesophagus.) 



Latin or Professional Name. 
Nervi intercostalis. 

Plexus cesophagens. 



55 


Network of nerves of lungs. 


Plexus pulmonalis. 


56 


Network of nerves of phar- 


Plexus pharyngens. 


57 


ynx. 
Lower jawbone. 


Os maxillare inferius. 


58 


Hyoid bone. 


Os hyoides. 


59 


Shoulder bone or clavicle. 


Clavicula. 


60 


First rib. 


Costa I. 


61 


Second rib. 


Costa II. 


62 


Eleventh rib. 


Costa XI. 


63 


Transverse process of the 


Processus transversus verte- 




loin backbone. 


brae lumbalis. 


64 


Sacrum bone. 


Os sacrum. 


65 


Pubis bone 


Os pubis (symphysis). 


66 


Large cheek muscle. 


Musculus zygomantieus 
major. 


67 


Lower digastric jaw muscle. 


Musculus digastricus maxil- 
lae inferioris. 


68 


Chewing muscle. 


Musculus masseter. 


69 


Salivary or parotid gland. 


Glandula parotis. 


70 


Under jaw gland. 


Glandula sub maxillaris. 


71 


Sterno-hyoid muscle. 


Musculus sterno-hyoidens. 


72 


Foremost scalene muscle. 


Musculus scalenus anticus. 


73 


Middle and posterior scal- 


Musculus scalenus medius 




ene muscle. 


et posticus. 


74 


Midriff. 


Diaphragm. 


75 


Square loin muscle. 


Musculus quadratus lum- 
borum. 


76 


Right bronchus. 


Bronchus dexter. 


77 


Kidney. 


Renes. 


78 


Upper kidney gland. 


Glandula supra renalis. 


79 


Gullet. 


(Esophagus. 


80 


Stomach. 


Stomachus. 


81 


Jejunum intestine. 


Intestinum jejunum. 


82 


Colon intestine. 


Intestinum #olon. 



NERVOUS SYSTEM. 



XI 



No. Common Namo. 

83 Rectum intestine. 

Si Bladder. 

85 Ureter. 

8fi Procumbent gland. 

87 Carrying vessel. 

8-^ Spermatic cord. 

89 Internal spermatic arteries 
and veins with network 
of internal spermatic 
nerves. 



Latin or Professional Name. 

Infest mum rectum. 

Vesica urinaria. 

Ureter. 

Glandula prostratus. 

Vas deferens. 

Chorda sperm atica. 

Arteria et vena spermatica 
con plexus spermaticus in- 
tern us. 



III. THE SENSE OF SMEEL. 



VERTICAL SECTION OF NASAL CAVITY. 



1 


Cavity in frontal bone. 


2 


Nasal bone. 


3 


Sphenoidal cavity. 


4 


Cribiform plate of the eth- 




moidal bone. 


5 


Upper jawbone. 


6 


Incisive canal. 


7 


Hard palate. 


8 


Palate molles against soft 




palate. 


9 


Tongue. 


10 


Nasal partition. 


11 


Posterior nasal cavity. 


12 


Roof of mouth. 


13 


Tonsils. 


14 


Pharyngeal palate arch. 


15 


Olfactory nerve. 


16 


Nasal-palate nerve of Scarpa. 



Sinus frontalis ossis frontis. 
Os nasi. 

Sinus sphenoidalis. 
Lamina cribrosa ossis eth- 

moidea. 
Os maxillare superioris. 
Canalis incivious. 
Palatum durum. 
Palatum molle v. velum 

palatinum. 
Lingua. 
Septum nasi. 
Posterior nares. 
Pharynx. 
Tonsilla. 

Arcus pharyngo — palatums. 
Nervus olfactorius. 
Nervus naso-palatinus scar- 



17 Incisive ganglion. 



Ganglion incisivum, 



Xll 



APPENDIX. 



IV. THE SENSE OF TASTE. 



NERVES OF PALATE AND TONGUE. 



No. 


Common Name. 


Latin or Professional Name. 


1 


Taste nerves. 


Nervi palatini. 


2 


Tongue and pharynx nerve. 


Nervus glosso-pharyugeus. 


3 


Branches of three-fold taste 


Bamus gustatorius nervi 




nerve. 


trigemini. 


4 


Branches of No. 2. 


Bamus nervi glosso-phar- 
yngei (pro. m. glosso-pala- 
tino). 


5 


Upper lip. 


Labium superioris. 


6 


Hard palate. 


Palatum durum. 


7 


Soft palate. 


Velum palatinum v. pa]atum 
molle. 


8 


Uvula. 


Uvula. 


9 


Side nerve of tongue. 


Arcus glosso-palatinue. 


10 


Arch of pharynx. 


Arcus pharyngo-palatinus. 


11 


Tonsil. 


Tonsilla. 


12 


Entrance to gullet. 


Isthmus faucium. 


13 


Boot of tongue. 


Badix lingua. 


14 


Tongue. 


Lingua. 



V. THE SENSE OF SIGHT. 



VERTICAL SECTION OF ORBIT AND GLOBE OF EYE, 



1 


Frontal bone. 




Os f rontis. 


2 


Upper jawbone. 




Os maxillare superius. 


3 


Fatty matter. 




Adipose tissue. 


4 


Frontal muscle. 




Musculus frontalis. 


5 


Upper eyelid. 




Palpebra superior. 


6 


Lower eyelid. 




Palpebra inferior. 


7 


Lower oblique eye 


muscle. 


Musculus obliquus oculi 
inferior. 


8 


Rectal eye muscle, lower. 


Musculus rectus oculi in- 








ferior. 



NERVOUS SYSTEM. 



Xlll 



No. 

9 

10 

11 

12 
13 

U 

15 

16 
17 

18 
19 
20 
21 
22 
23 
24 
25 
26 



Rectal eye muscle, external 

Rectal eye muscle, upper. 

Upper eyelid muscle. 

Eye nerve. 
Coujunctiou of Eyelids. 



Latin or Profpssional Name. 

Musculus rectus oculi, ex- 
ternus. 

Musculus rectus oculi su- 
perior. 

Musculus levator palpebral 
superior. 

Nervoa opticus. 

CDnjunctiva palpebrae. 



Rejection of conjunction from inner surface of eyelids to 
globe. 



Conjunction of eyelids and 

white of eye. 
Conjunction of'cornea. 
Strong horny membrane 

forming outer part of eye. 
Membrane of aqueous humor, lining anterior chamber. 



Conjunctiva sclerotica (bul- 

bi.) 
Conjunctiva cornea. 

Cornea. 



Anterior camera. 

Posterior camera. 

Sinus of iris. 

Sclerotic tunic. 

Crystalline lens. 

Ciliary body. 

Vitreous body, glassy matter. 

Tunic of the retina. 

Tunic of the choroid, 



Camera oculi anterior. 
Camera oculi posterior. 
Sinus venosis iridis. 
Tunica sclerotica. 
Lens crystallina. 
Corpus ciliare. 
Corpus vitreum. 
Tunica retina. 
Tunica choroidea. 



VI THE SENSE OF HEARING. 

THE INTERNAL. ORGANS OF HEARING EXPOSED 
WITHOUT BONY STRUCTURES. 



1 


External ear. 




Auricula externa. 


2 


Auditory canal. 




Meatus auditor, externus. 


3 


Tympanum. 




Membrana tympani. 


4 


Hammer. 




Malleus. 


5 


Handle of same, 


long. 


Processus longus mallei. 



XIV 



APPENDIX. 



No. Common Name. 

6 Mannubrium of hammer. 

7 Anvil. 

8 Short process of same. 

9 Long process of same. 

10 Orbicular ossicle. 

11 Stapes. 

12 Vestibule. 

13 Upper semicircular canal. 

14 Posterior semicircular canal. 

15 Lower semicircular canal. 

16 Shell, spiral cavity. 

17 Cupok of shell. 



Latin or Professional Name. 

Mannubrium mallei. 

Incus. 

Processus brevis incudis. 

Processus longus incudis. 

Ossiculum orbiculare Silvii. 

Stapes. 

Vestibulum. 

Canalis semicircularis su- 
perior. 

Canalis semicircularis pos- 
terior. 

Canalis semicircularis in- 
ferior. 

Cochlea. 

Cupola cochleae. 




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nished with a lock and 
key to protect contents. 







.. , ■ 












* 
'-.// 












.:■/'- - 






T'JIHaMV JO S3XYXS (iaXIiNLIl 



'SS3a9Noo jo AMvaan 






